Seiko 5 vs. Seiko Prospex [Budget, Quality, Movements, & More]

In the eyes of many consumers, Seiko has always been associated with value. They have consistently offered a variety of watches at different price points and consistently high quality. As one of the few completely integrated manufacturers, Seiko offers a wide range of consumers the opportunity to own a fully in-house watch. 

Prior to 2010, Seiko’s high-end brand Grand Seiko was not available in Japan, and it was not until 2018 that Grand Seiko opened a corporate office in the United States. With that came other corporate changes and rebranding.

Some of Seiko’s most famous models, such as the SKX, Monster, Samurai, and Turtle, were originally part of their standard offerings. Today, descendants of those enthusiast favorites exist in the Seiko 5 and Seiko Prospex brands.

The Purpose of Seiko 5

The original purpose of the Seiko 5 brand was to offer consumers a very affordable mechanical watch with five key features; a self-winding movement, a day-date display at 3 o’clock, water resistance, a crown at 4 o’clock, and a case and bracelet built for durability.

The original Seiko 5 watches all had these features, with models from the recent past resembling pseudo-dive watches, often with 100m of water resistance, to more casual and dress-oriented watches with 30 to 50m of water resistance. 

In 2019, Seiko relaunched the Seiko 5 brand with a line of watches resembling the SKX collection. The SKX007, along with other variants of the beloved dive watch, was a consumer hit for many years. It could easily be found at an affordable price and had proved itself to be extremely reliable.

They were full-fledged dive watches with ISO certification, 200 meters of water resistance, a screw-down crown, and a uni-directional rotating bezel. The new Seiko 5 SRPD line of watches offered much more variety in terms of colors and bracelet options, but they only had 100m of water resistance and a push-pull crown.

While the new SRPD series kept the SKX style, they also marked the discontinuation of the SKX line. While Seiko 5 as a whole is aimed to be more of a mass-market product than the SKX series, many enthusiasts lament the replacement. The Seiko 5 line now offers other models that include smooth-bezel options to the SKX-inspired design, a GMT complication, and field-inspired watches.

With that, Seiko has drifted away from the original 5 characteristics, with the GMT model not having a day function and the field watches having 3 o’clock crowns. They have maintained their affordability and durability, being more than capable as everyday watches for most people, and aimed at new enthusiasts and those wanting a mechanical timepiece for an affordable price. 

The Purpose of Seiko Prospex

Seiko’s history of making modern tool watches starts with its first purpose-built dive watch released in 1965. Since then, Seiko has been an innovator in diving technologies, including developing the first wrist-worn dive computer in 1990.

The Prospex line is Seiko’s professionally oriented watch line. Prospex focuses on dive watches, but there are others, including a variety of field watches, chronographs, and ana-digi models (watches with both analog and digital displays). 

Included in the recent reorganization of Seiko’s model lineup is the Prospex line. Initially reserved for the most rugged sports watches, Seiko has relaunched much-loved models such as the Turtle, Monster, Samurai, and Sumo. Once part of the standard Seiko dive watch offerings, these models were updated and are now part of the Prospex model line. 

With that came a price increase, but the inclusion of sapphire crystals, ceramic bezels, and upgraded dials made the price increase worthwhile. Even though these models are more expensive, they are still affordable, often found for under $750.

Seiko has created space within the Prospex line for high-end watches. Ranging from mechanical chronograph movements to high-end Spring-Drive divers and GMTs that share movements with Grand Seiko, these watches have retail prices over $3000. The Prospex line aims to make some of the best sports timepieces available at various prices. 

Seiko 5 or Prospex?

Budget

Since forum readings and many watch enthusiasts have all pointed towards Seiko as the best value for money, your budget is the first thing to consider. While prices under $1,000 are considered entry-level in the broader watch-collecting hobby, the difference between $300 and $600 can be staggering.

Twice the money does not buy twice the watch (unless you are buying two pieces). Other factors should be taken into account when determining your next watch-buying goal, but having firm financial guidelines will be extremely helpful. 

Build Quality

While doubling the price does not necessarily increase the quality, a price increase does improve many of the watch’s aspects. Comparing the SRPD51 to the SRPE05, even though they both have the same movement, the crystal and bezel of the SRPE05 are upgraded compared to the SRPD51 (sapphire versus mineral for the crystal, ceramic versus aluminum for the bezel). 

The SRPE05 is also rated to 200m of water resistance compared to the SRPD51’s 100m, making the SRPE05 a true dive watch. The 100m rating and lack of a screw-down crown on the SRPD51 make it only suitable for casual water usage (surface swimming, maybe some shallow diving).

If these upgrades are considered worthwhile, it may be worth saving a little longer to get the SRPE05 from the Prospex line. If style is the top concern, the Seiko 5 will serve well. Aside from the more easily discernible aspects, there will be many differences in quality between the Seiko 5 line and the Prospex line.

The Prospex line will have a range of quality case finishing and bracelets, from slightly better than the Seiko 5 line to competing with higher-end luxury brands. Comparing the SPB155 (Prospex) to the SRPG29 (Seiko 5), the case finishing and bracelet quality of the SPB155 is a notable upgrade over the SRPG29. The straps and buckles on the Prospex models will also be an improvement over the Seiko 5 models.

Movements

As mentioned earlier, the movement quality in the Prospex range can vary significantly compared to Seiko 5. Entry-level Prospex can have the same movements as the Seiko 5 range. In contrast, mid-tier and high-end Prospex models can have more well-regulated movements and finish than what is available in Seiko 5 models. The Prospex range also includes a variety of quartz models, including time and date divers, ana-digi models, and solar-powered chronographs. 

Availability

Finally, the Seiko 5 models are more widely available. In the United States, many Seiko 5 models can be found in shopping malls and department stores in almost every town and city. Entry-level Prospex models will likely be available in many moderate to large-size markets, but finding a store with higher-end Prospex models will be more difficult.

If buying in person is a must, this can be problematic. Fortunately, internet access and a global economy have made access to even the most hard-to-come-by models possible. The most important aspect of purchasing a watch is whether or not it resonates with the end user. From there, factors such as use case, desired traits, and budget can filter and help inform the final decision. 

Seiko 5 and Prospex Collections

Seiko 5 SRPD

The SRPD lineup consists of watches most closely resembling the original SKX line. Inside all of them is the caliber 4R36, which hacks, hand-winds, and offers 41 hours of power reserve. They all have 10 bar of water resistance (equivalent to 100 meters of static pressure), a unidirectional bezel, mineral crystal, and a display case back. These watches are 42.5mm wide, 13.4mm thick, have 22mm lugs, and are 46mm lug to lug.

A model such as the SRPD55 will be the most conservative offering, with a conventional black dial with silver outlined indices and hands with white lume. The SRPD55 comes on a 3-link style bracelet instead of a more ornate 5-link style seen on the original SKX line. It is one of the most versatile watches in this collection but could be viewed as stale compared to other models. The SRPD55 retails for $295.

The SRPD71 is more stylized than the SRPD55, with a blue dial and bezel, white chapter ring, and vintage-inspired tan lume on the indices and hands. This model is under the “SKX Suits Style” collection, suggesting that this watch is intended to be more stylish than utilitarian with the colored dial elements and Milanese strap. The SRPD71 commands a slight premium at $350 retail.

One of the more significant departures from the original SKX line is the SRPD81. With a completely black case, dial, and bezel, with blue lume and bezel markings, this model takes influence from enthusiasts that modified their SKX watches. Aftermarket suppliers would create parts that allowed collectors to alter their timepieces and make them their own.

With colored lume, black cases, and different strap offerings, models such as the SRPD81 enable consumers to have these more unique offerings direct from the original manufacturer. Even though it does not come on a metal bracelet, the other aesthetic changes increase the retail price to $335.

Seiko 5 SRPG Collection

The Seiko 5 SRPG collection consists of the brand’s field watch offerings. A long-standing style in the Seiko 5 collection, even before the brand revamp, the biggest departure is the movement of the crown position. The current Seiko 5 SRPG watches have their crowns at 3 o’clock instead of 4 o’clock, which is typical for Seiko 5. 

The SRPG watches still maintain other hallmarks of the Seiko 5 collection with the day-date feature, water resistance, mechanical movement, and durable case design. These watches have the same 4R36 movement, 10 bar water resistance rating, mineral crystal, and display case back as the SRPD series. The SRPG Field watches measure 39.4mm wide, 13.2mm thick, have 20mm lugs, and measure 48.1mm lug to lug. 

The SRPG29 comes with a blue dial, silver indices and hands with white lume, and a 3-link style metal bracelet. The dial layout is typical for a field watch, with large numerals to facilitate reading the time. There is a 24-hour inner track on the dial, allowing for easier reading of 24-hour time. The SRPG29 retails for $275.

Keeping the same dial layout and case as the SRPG29, the SRPG31 comes with a blue-grey textured and a matching colored textile strap. The color is more muted than the SRPG29, making the watch better suited for casual situations, especially with the textile strap. The SRPG31 retails for $275.

The SRPG41 is further stylized, adding a textured dial that also mimics a faded look, with a lighter dial color in the center and progressing to a darker color towards the outer edges. The press photos make this look more pronounced.

In real life, this color differentiation varies depending on lighting, ranging from utterly dark grey to a more pronounced brown-to-black fade. The lume is also vintage-inspired with a light tan coloration, and the case is covered with a black hard coating. Coming on a leather strap, this is another more style-oriented model than a function-focused one. The SRPG41 retails for $315.

Seiko 5 Sports GMT Collection

Released in 2022, the SSK series launched to a world that was excited to travel. These watches use the same case design as the SKX, measuring 42.5mm wide, 13.6mm thick, 22mm wide bracelets, 46mm lug-to-lug, mineral crystals, and are rated to 10 bar of water resistance. These watches come on a 5-link style bracelet, closer in style to the original bracelets found on the SKX. 

The launch of this watch also unveiled the new 4R34 movement, which has an adjustable 24-hour hand, allowing for the tracking of multiple time zones, in addition to the rotating 24-hour bezel. This combination allowed for a very affordable dual-time watch from a notable brand, as many Swiss brands are easily twice as expensive for a dual-time zone timepiece. 

The SSK series comes in three dial colors, black (SSK001), blue (SSK003), and orange (SSK005). They each have two-toned bezels, with the blue being the most pronounced and the orange and black being more subtle, and they vary depending on the lighting.

These watches also depart from the Seiko 5 tradition, removing the day complication at 3 o’clock but maintaining the date. They also now have a date magnifier, which allows for easier reading of the date.  Regardless of color variant, each of these watches retails for $475. 

Seiko Prospex Alpinist

The Seiko Alpinist has long been an enthusiast favorite. It offers a more rugged alternative to conventional time and date watches, such as the SARB033. The inner rotating bezel controlled by the crown at 4 o’clock is meant to be used as a manual compass but can also be utilized to time events, similar to a dive bezel.

The iconic model for the Alpinist line is the variant with a green dial alongside gold indices and hands. When Seiko relaunched the Alpinist as part of the Prospex line, it was released as the SPB121. The SPB121 measures 39.5mm wide, 13.2mm thick, and 46.4mm lug-to-lug. It has a 20mm wide strap and contains the 6R35 movement that has a 70-hour power reserve, date function, hacks, and hand winds.

The case has 20 bar of water resistance, facilitated by a screw-down crown. The front crystal is sapphire, and the clasp is a deployant style instead of a pin and buckle, as seen on the Seiko 5 models. The SPB121 retails for $725. Should a green dial not do the trick, other dial, strap, and bracelet options are available. 

Should the general style of the Seiko Prospex Alpinist be appealing, but the second crown of the SPB121 is off-putting, the SPB243 should be considered. Slightly smaller at 38mm wide, 12.9mm thick, 19mm lugs, and 46.2mm lug-to-lug, these dimensions allow the watch to be more svelte on the wrist. The SPB243 uses the same 6R35 movement and has 20 bar of water resistance with a screw-down crown. 

The dark sunburst dial covered by a sapphire crystal will be more flexible than the green dial with various attire, and the lack of the date magnifier will be a plus for many buyers. To appeal to the vintage origins of the original Alpinist from 1959, the lume is done in a faux-patina color. The SPB243 retails for $750. Again, other dial, strap, and bracelet options are available. 

To display the higher end of the Seiko Prospex range, there is the SJE085. In 2021, Seiko launched a limited edition recreation of the original 1959 Alpinist. They took inspiration from the original, incorporating elements from the original dial design and the jagged stitching on the bund-style strap.

The SJE085 measures 36.6mm wide and 11.1mm thick, with 18mm lugs, and 43.8mm lug-to-lug. The movement inside is Seiko’s 6L35, which has a higher accuracy rating than the 6R34 and is intended to be a more high-end movement, sitting below those from Grand Seiko. 

The SJE085 has 10 bar of water resistance, less than other Prospex models, but is more than enough for daily wear. The case is also more finely finished, all in high polish, which will make it easy to wear with a suit with a change of strap. It was a limited edition of 1,959 pieces, making availability difficult. The original retail was $2,900, but used prices have settled south of that mark. There are also deals to be had on models still in inventory.

Seiko Prospex Dive Watches

In the Prospex line, we see modern versions of many of Seiko’s mainstay models, such as the Samurai, Sumo, and Turtle. Seiko could rely on the popularity of those models alone, but in 2022, they released the Prospex Diver Re-Interpretation. 

Offered in a variety of colors, strap, and bracelet options, this watch does combine several elements from various favorite Seiko dive watch models and molds them into a new and unique design that stands on its own. Measuring 41mm wide, 12.3mm thick, 20mm lugs, and 46.9mm lug to lug, it is one of the more wearable Seiko divers and is the thinnest one they’ve ever made.

The watch is rated at 200 meters of water resistance and is an ISO-certified diver. Inside is the Seiko 6R35 movement. The Seiko Prospex SPB317 featured here has a black dial and black rubber strap. The retail price is $900, and slightly more for models on a bracelet.

Another modern re-interpretation is the SPB301 Save The Ocean special edition. This case shape has been nicknamed Captain Willard as this watch resembles the watch famously seen in the movie Apocalypse Now. The SPB301 measures 42.7mm wide, 13mm thick, 46.6mm lug-to-lug, and has 20mm lugs.

Inside is the 6R35, and the SPB301 is ISO-Certified, rated at 200 meters of water resistance. This version stands out with its grained white dial, reminiscent of the Grand Seiko White Birch dial, and textured blue bezel. The SPB301 retails for $1,300. 

Towards the top of the Seiko Prospex dive watch range is the impressive SNR029. Representing the Spring Drive equipped models from the Prospex range, the SNR029 features a titanium case and bracelet with Seiko’s proprietary “super-hard” coating to protect from scratches.

Equally impressive are the dimensions, as the case measures 44.8mm wide, 14.7mm thick, and 50.9mm lug-to-lug. The relatively short lug-to-lug measurement will make it wearable for most people. The SNR029 is still a very large watch. 

The SNR029 is rated at 300m of water resistance and is ISO-certified for saturation diving, giving the SNR029 improved capabilities over the standard Prospex Divers. Inside is the Seiko 5R65 Spring Drive movement, rated at +/-1 second per day, and offers a 72-hour power reserve that can be tracked via the indicator on the dial. It also has a very cool ratcheting clasp system to allow for minor adjustments and to fit the watch over a wetsuit. The SNR029 retails at $6,000 and is among the best of what Seiko has to offer.

Seiko Prospex Speedtimer Watches

Drawing on Seiko’s history with timing sporting events, the Speedtimer collection references their first watch with their Caliber 6139, the world’s first automatic chronograph with a column-wheel and vertical clutch. 

Representing the line of mechanical Speedtimers, the SRQ037 was released in 2021 as part of Seiko’s unveiling of the Prospex Speedtimer collection. Inside is the 8R46 automatic caliber, a 30-minute chronograph with a column wheel and vertical clutch. The 8R46 has a rated accuracy of +25/-15 sec per day and a 45-hour power reserve.

The mechanical Speedtimers measure 15.1mm thick, 42.5mm wide, 50mm lug-to-lug, and 20mm lugs, and have a water resistance rating of 10 bar. The SRQ037 specifically comes with a black dial, tan faux-vintage colored lume, and a metal bracelet. The Seiko Prospex Speedtimer SRQ037 retails for $3,000 

Offering a more accessible approach to the chronograph, the Seiko Prospex Speedtimer Solar Chronograph collection has quickly become an enthusiast favorite. Focusing on the SSC813, the dial is white with black subdials and blackened hands and indices.

The Speedtimer Solar Chronographs use the solar-powered V192 quartz movement, allowing for an accuracy rating of +/-15 seconds a month. The chronograph measures up to 60 minutes and includes a 24-hour indicator for the displayed time at 3 o’clock.

The case measures 13mm thick, 39mm wide, 45.5mm lug-to-lug, has 20mm lugs, and is rated to 10 bar of water resistance. The size, finishing, and the more affordable retail price of $675 have made it a fast favorite in the broader Seiko Prospex collection. 

Should the SSC813 be too small, there are the larger Prospex Speedtimer Solar Chronographs. Compared to the SSC913, the case holds the same movement and has the same 10 bar of water resistance but measures 13mm thick, 41.4mm wide, 45.9mm lug-to-lug, and has 21mm lugs.

The SSC913 has a blue dial with red accents for the running seconds, chronograph seconds hands, and part of the tachymeter bezel. The slight increase in size will be preferable for those who have grown accustomed to larger watches, but the still restrained 45.9mm lug-to-lug allows it to be worn and a wide variety of wrists.

There is a slight price increase to $700, but the choice between the different solar-powered Speedtimers should be based on size and color preference. 

Spoiled for Choice

Seiko has cultivated its following in enthusiast circles based on its track record of building dependable watches. When looking for a sporty watch, buyers have many options in the Seiko 5 and Prospex collections.

Instead of one being overwhelmingly better than the other, it is more a matter of style preference, desired features, and overall budget. Given the number of options available between the Seiko 5 and Prospex collections, there should be something for almost every buyer.