Measurements

Even though a lot of enthusiasts rip on Steinhart for their unoriginal design, they at least have the decency to give the Ocean One a different size. This might not seem like a big deal, but it's something a lot of collectors were looking for.

Indeed, Rolex is known to manufacture mostly small to medium timepieces, so men with large wrists can feel a bit left out. For men with big (7''+) wrists, the Steinhart Ocean One might actually look better than the Rolex Sub.

Not only is the case larger, but you also get a 22mm lug width and a slightly thicker frame, which all contribute to the bulkier feel of the Ocean One. If you happen to have smaller wrists but still want the Steinhart, it's also available with a 39mm diameter.

Specifications

Crystal

The crystal of the two watches might look similar at first sight; they are both flat sapphire crystals with a magnification lens over the date display. 

The major difference is the anti-reflective coating, or lack thereof. The Rolex Sub doesn't have any AR-coating on its crystal. Some say it's not necessary since flat crystals aren't as reflective as domed crystals. Other people think Rolex simply likes the attention-grab of shiny glass.

Steinhart isn't having it with sapphire's reflectiveness, so they decided to apply not one, but two layers of anti-reflective coating inside the crystal. This reduces the reflectiveness without ruining the scratch resistance of sapphire.

Water Resistance & Crown

It's no secret, the Rolex Submariner is a diver's watch. This means that water resistance is extremely important both for the Sub itself and for anyone who tries to replicate the styling. 

Of course, the Rolex Sub and the Steinhart Ocean One are equipped with a screw-down crown. Rolex uses its Triplock crown system, while Steinhart's crown doesn't have any fancy name.

They both do the job perfectly fine, as the two are rated for 300m of water resistance. This means that you will be able to take your watch for recreational and even professional diving. 

As far as styling goes, the two crowns share the same coin-edge pattern with the company's respective logo engraved on top.

Bezel

Once again, the bezel of the two watches is virtually indistinguishable, but there are a few key differences. For instance, the Sub is only offered with Rolex's Cerachrom (ceramic) bezel insert, whereas the Steinhart Ocean One can be equipped with an aluminum insert or with a ceramic insert (for 35€ more).

The two bezels are powered by a 120-click unidirectional mechanism with a 60-minute scale, but one is clearly superior. Rolex is undoubtedly the king of bezel mechanisms, and even high-end companies like Omega can't match Rolex in terms of crispness. 

Of course, Steinhart's bezel isn't as good as the Sub's, but it works perfectly fine and there's almost no play.

Lume

We can all agree that luminous phosphorescent is one of the most important features of a dive watch. Knowing that, Rolex and Steinhart brought their A-game for the Sub and Ocean One.

Rolex applied its own Chromalight application, which will glow in a bright blue color. This lume is known to glow brightly and last for several hours.

On the other hand, Steinhart went with a Superluminova application, which is renowned for its high quality. They chose the BGW9 application, which is the second brightest in Superluminova's lineup. It's about 5% duller than the C3 lume, but it gives off a whiter glow during daytime.

Both watches have hands & indices coated with lume, but the bezel's application is slightly different.  The Ocean One gets a fully lumed triangle, whereas the Submariner only gets a lume pip.

Movement

When you spend a considerable amount of money on a watch, you most likely pay attention to what makes its heart beat.

The two watches compared today are powered by a Swiss-made movement. The 3135 Caliber is an in-house movement manufactured by Rolex, whereas the 2824-2 Caliber is mass-produced by the famous ETA company.

As far as functions go, the 3135 and the ETA 2824-2 are on the same level. With both movements, you get an automatic caliber that can also be hand-wound and hacked. They both beat at the same high frequency, but the Rolex's power reserve is a bit more substantial.

Like almost every Rolex watch, the Submariner gets a -2 to +2 sec/day accuracy rating, which earns it the COSC certification. Unfortunately, it doesn't meet the METAS criteria, as it requires +0 to +5 secs/day accuracy.

The ETA 2824-2 used in the Steinhart Ocean One is the "elaborated" grade, which corresponds to a +- 7 secs/day accuracy. It's not as accurate as the Rolex nor does it get any certification, but it's still a damn good movement that is extremely reliable.

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One of the most important factors that should determine your decision is your ability to afford the maintenance cost of these watches. After 5-8 years, your mechanical movement will need to be serviced.

For the ETA 2824, your neighborhood watch store will be able to do it for $140-$180. On the other hand, the Rolex's service will certainly be more expensive than the Steinhart Ocean One itself ($600+ for a professional service.)

Design

Dial

The dials of the Submariner and the Ocean One are basically indistinguishable. There're two main ways to differentiate them: the logo at the top and the fonts at the bottom. 

Even looking at the logo can be a bit confusing from afar since Steinhart's logo is also crown-shaped. The dial's text is where you can separate the two watches. The first line is the respective model name, while the second line of text says 1000ft / 300m for both.

The last line of text for the Rolex is "Superlative Chronometer Officially Certified", which is something Steinhart can't brag about. Instead, the Ocean One displays an "Automatic Movement Professional" script.

Hands & Indices

Once again, the hands & indices are pretty much the same on the two timepieces. The biggest difference is the 12 o'clock mark. Both share a triangle shape, but the Steinhart's triangle is a bit slimmer and elongated, which makes it look similar to the Tudor Black Bay.

Apart from that, everything is pretty much the same, from the Mercedes hands set to the circle and rectangular indices.

Case

The case is probably the element that's the easiest to distinguish between the Submariner and the Ocean One. First, Rolex's case is made from Oystersteel, which is their branded version of 904L steel.

Conversely, the Steinhart Ocean One is equipped with a conventional 316L stainless steel case. The only notable advantage of 904L over 316L is the high resistance to corrosion. Also, 904L can be polished more intensively, making it shinier.

The shape of the case also differs in a meaningful way between the two watches. The Rolex Submariner is the stockiest of the two: both the lugs and the crown guards are thick and square.

On the other hand, the Steinhart Ocean Once gets slender curves: the lugs are thin and pointy, and so are the crown guards. 

The difference in case shape is not something you notice at first sight, but it does make a huge difference once you get accustomed to one or the other styling.

Bracelet

Once again, the bracelet is made of 904L Oystersteel for the Rolex and 316L stainless steel for the Steinhart. While the two bracelets are comfortable and have a high-quality feel, Rolex clearly beats Steinhart in this department.

This doesn't mean that the Ocean One's bracelet is bad, it's simply normal for the Sub to have a higher quality bracelet considering the large price difference. 

You get the same basic specs on both bracelets: multiple micro-adjustments, solid end-links, folded clasp, etc.. Also, both watches sport a fully brushed look.

Value