Another Sunday, another showdown! This week, we’ll dive headfirst into the world of luxury dive watches, and two examples with legendary lineage will go head to head. The first is the latest iteration of the Rolex Sea-Dweller, a watch that finds its roots in the late 1960s as the professional brother of the Submariner. The second is the brand-new Blancpain Fifty Fathoms Tech BOC IV. The origins of the Fifty Fathoms go back to the early 1950s when Blancpain introduced the first version of this iconic dive watch. But this battle is not about the glory of the past. It’s all about which watch can take the crown now as a modern luxury diver.

Today’s battle is a funny one. Both Blancpain and Rolex are proper luxury watch brands that take great pride in developing serious dive watches. Nevertheless, there is a difference in perception among a wider audience. It is safe to say that the Sea-Dweller is a luxury watch first and a diver second. With the Fifty Fathoms Tech BOC IV, Blancpain created a super-capable modern diver first and a luxury watch second. This perception will undoubtedly play a part in today’s battle. The biggest elephant in the room might be the price difference, though. The Rolex Sea-Dweller comes in at €13,900, whereas Blancpain asks a hefty sum of €23,250 for the Fifty Fathoms Tech BOC IV.

King Seiko Vanac propped up on book

Last week, on Sunday Morning Showdown…

Before Mike and Jorg kick off this week’s battle, let’s quickly look at last week’s results. In last week’s Sunday Morning Showdown, the new King Seiko Vanac took the win over the Toledano & Chan B/1 by the slightest margin. The King Seiko received 51% of your votes versus 49% for the Toledano & Chan. Reading the comments clearly showed that quite a few of you wouldn’t want either. For those who did have a favorite, though, the Toledano & Chan seemed to be the winner. Well, in the end, the numbers don’t lie, and they show that the new Vanac took last week’s victory. Let’s see what this week has in store. Over to Mike and Jorg!

Blancpain Fifty Fathoms Tech BOC IV header image

Jorg: Blancpain Fifty Fathoms Tech BOC IV

I have the thankless task of opening this week’s battle with a watch that is a whole €9,350 more expensive than its opponent. Do I think that’s a handicap? You bet! For many, picking an option close to half the price is obvious, especially if the more affordable option is a Rolex. But the great thing about this series is that we’re spending imaginary money, so anything can happen. Of course, that begs the question of whether I would genuinely pick the Fifty Fathoms Tech BOC IV over the Sea-Dweller, especially since the Sea-Dweller ref. 16600 is the one Rolex I am after.

Blancpain Fifty Fathoms Tech BOC IV pocket shot

I would be lying if I claimed I didn’t have my reservations. But coming off the high of spending time with the Fifty Fathom BOC IV, I can genuinely say that I have become a fan of the watch. It is what the modern Fifty Fathoms should be. It offers a perfect mix of the famous looks of the first Fifty Fathoms from the early 1950s and a thoroughly modern take on that classic watch. This perfect marriage of the two is one of the strongest features of this new limited-edition Fifty Fathoms.

Blancpain Fifty Fathoms Tech BOC IV lume shot

Combining the best of two worlds

As I explained in my review, I was a fan of the Fifty Fathoms 70th Anniversary Act 3 and the Tech Gombessa, which both debuted as part of Blancpain’s 70th-anniversary celebrations for the Fifty Fathoms. Whereas the first was a great watch to celebrate the classic dive icon (if only Blancpain would release a regular stainless steel production version of that watch!), the second showed what the modern Fifty Fathoms could look like. The 47mm watch was developed with serious diving challenges in mind and featured a three-hour dive bezel and a corresponding hand, which Blancpain developed for closed-circuit tech divers.

Blancpain Fifty Fathoms Tech BOC IV

Blancpain took that watch as the inspiration for its new Fifty Fathoms Tech BOC IV. It keeps the style of the Gombessa, tones down the size, and loses the 180-minute dive bezel and the extra hand. What remains is a beautifully sculpted watch that took me by surprise. I have criticized Blancpain for squandering its icon’s great legacy and thought I hadn’t seen how it could improve yet. But after spending time with this new Tech BOC IV, I am sure it is the way forward for the modern Fifty Fathoms models.

Blancpain Fifty Fathoms Tech BOC IV bezel from side

A superbly designed modern case

The watch has a nicely sculpted 45mm titanium case with a 14.1mm thickness. This case shows a great eye for design. Essentially, it is divided into three parts. The lower and middle portions of the “folded” case flanks make up roughly two-thirds of the thickness, while the upper third is the unidirectional bezel. I was seriously impressed by the design and execution. First, if you let your eyes go from the integrated rubber strap to the case, you will see a sharp line dividing the lower and middle portions. That same line continues on the rubber strap for a brilliant natural flow.

Blancpain Fifty Fathoms Tech BOC IV case profile

Additionally, the flow from the strap to the case is seamless thanks to the central “lugs” and the brilliant production quality. As a result, the strap’s left and right sides hug the case flanks beautifully. This level of detail and quality shows Blancpain’s superb craftsmanship.

Blancpain Fifty Fathoms Tech BOC IV case profile, crown side

Furthermore, the attention to detail is spectacular and not seen on many watches in the same category. From the beautifully finished case to the integration of the helium escape valve and the perfectly angular crown guards, it’s clear that Blancpain left no detail unconsidered. This is what truly made me feel like Blancpain is a proper step up from many of the brands we associate with modern luxury dive watches, including Rolex.

Blancpain Fifty Fathoms Tech BOC IV case back and caliber 1315A

The finer points of the Fifty Fathoms Tech BOC IV

That also becomes apparent with the movement. We all know the caliber powering any Rolex tool watch is built like a tank. But if you want a proper step up in watchmaking, the Blancpain’s in-house caliber 1315A offers just that. The automatic movement comprises 227 parts, has 35 jewels, and provides 120 hours of power reserve. Furthermore, it features a Glucydur free-sprung balance with gold regulation screws as well as a sweeping brushed finish and polished bevels on the bridges. The skeletonized rotor has the brand’s engraved Ocean Commitment logo, a nice touch linking the watch to Blancpain’s mission to preserve marine life.

This is the only directly visible sign of its active links to the world of diving, but once you put the watch on the wrist, it feels like a proper tool. An incredibly nicely designed and expertly made one, I might add. At its core, this feels much more like a watch developed for its intended purpose than the Sea-Dweller. I find romance in that, and it shapes my preference. Plus, wearing the 45mm case pleasantly surprised me. While it might seem dauntingly large at first, I can confirm that it feels smaller than its diameter suggests. Thanks to the central strap connectors, there are no traditional lugs to make the case longer. This makes the Fifty Fathoms Tech BOC IV feel like a 42mm watch, which was a great surprise.

Blancpain Fifty Fathoms Tech BOC IV pocket shot

Wearing is believing

Due to its design, the watch wears better than many 40mm+ luxury divers, including the Seamaster Diver 300M and the current Sea-Dweller. The beautifully shaped rubber strap also makes wearing the fairly lightweight titanium Fifty Fathoms BOC IV a joy. That’s how the watch completely won me over. It presents itself as an incredibly well-made and intelligently considered product that uses Blancpain’s luxury watchmaking chops to be a better dive watch. This creates a far more personal connection than I could have imagined or could ever have with the current Sea-Dweller.

The reason is simple: I don’t want the current Sea-Dweller. I’m after the older, smaller Sea-Dweller ref. 16600. And even if we look at the current Rolex collection of tool watches, I would pick the titanium Yacht-Master 42 over the Sea-Dweller in a heartbeat. After that, I would even choose the Submariner over the Sea-Dweller. When it comes time to pick a professional dive watch that could serve as a daily wearer, I would undoubtedly take the Blancpain Fifty Fathoms BOC IV.

Blancpain Fifty Fathoms Tech BOC IV pocket shot

I understand that not that many of the Fratelli might think the same. But to understand the magic of the Fifty Fathoms BOC IV, you have to see it in real life and wear it. Then you will understand why this far more expensive option is my pick. It’s due to a personal connection from experience that is far more powerful than any preconceived notion of which of the two is better. But go ahead, Mike; tell our readers why you think the Rolex Sea-Dweller ref. 126600 should win this battle.

Rolex Sea-Dweller ref. 126600 dial close-up

Image: The Watch Club

Mike: Rolex Sea-Dweller ref. 126600

Thanks, Jorg. For me, this Sunday Morning Showdown is an absolute layup. The Blancpain Fifty Fathoms is a fine watch, but there’s no world in which I’d choose it over the Rolex Sea-Dweller 126600. Even though the Sea-Dweller 126600 is not my favorite Rolex diver by a long shot, let me explain why I like it so much more than the latest Fifty Fathoms.

Rolex Sea-Dweller ref. 126600 diagonal view

Image: Watch Club

There are oodles of Rolex haters out there who love to talk about how boring the brand’s watches are and how they rarely change. Those sentiments mean little to me because Rolex dive watches don’t need to change. They’re the standard bearers and define what a diver should look like. Compare the current Sea-Dweller to the Fifty Fathoms Tech BOC IV, and it’s hard not to look at the hockey puck with its oddball lug design as little more than a gimmick.

A rock-solid and well-made watch

Let’s also remind ourselves that Rolex’s build quality is second to none. Sure, the brand is everywhere and maybe isn’t viewed as a creative or original choice. Yet, even with the company’s success, there’s no evidence of resting on laurels and making subpar watches. Controls like the bezel and screw-down crown all feel perfectly weighted and exact. Considering that a Rolex diver is a mass-market product, I’m convinced no brand does it better.

Rolex Sea-Dweller ref. 126600 lume shot

Image: The Watch Club

Consider the dial and bezel details on the Sea-Dweller. Flaws are difficult to find. The blue Chromalight shines brightly in the dark, allowing owners to avoid typical reservation-filled conversations with lines like, “It’s a great watch, but the lume stinks.” We can complain about the Cyclops above the date, but it’s actually an ode to continuous improvement. When the 126600 debuted in 2017, Rolex stated that it took decades to create a crystal with its signature magnifying feature that could withstand the pressure at 1,220 meters. If the Cyclops isn’t lovable, perhaps the throwback red dial text makes up for it. It was a good move and adds a dose of charm to this professional-grade dive watch.

Rolex Sea-Dweller ref. 126600 bracelet with clasp closed

Image: The Watch Club

The best bracelet in the game?

On one hand, Rolex deserves enormous credit for producing the best bracelets in the watch industry. On the other hand, it’s depressing that other brands continue to stumble and fall when designing these crucial accessories. In today’s showdown, Blancpain takes the easy way out with rubber. That might be preferable for a dive, but I want more metal at these prices. The Oyster bracelet with its Oysterlock clasp and Glidelock toolless adjustment system is peerless. The links are beautifully finished, and with Rolex, there’s never a sharp edge unless it’s supposed to be there. In the end, the bracelet also allows this tool watch to survive in a business setting, whereas the Blancpain comes off as too sporty and casual.

Rolex Sea-Dweller ref. 126600 case flank and helium valve

Image: The Watch Club

A bulletproof movement

Rolex has included its 3235 automatic caliber within the Sea-Dweller’s helium-valve-equipped stainless steel case. The movement is down on power reserve versus the Blancpain with “just” 70 hours. However, the chronometer caliber has an accuracy of ±2 seconds per day after casing.

Rolex Sea-Dweller ref. 126600 dial macro shot

Image: The Watch Club

Large and commanding

While the Sea-Dweller is a bit large for me, the 43mm by 50mm case is a compelling option for those with medium to large wrists. At 15.5mm thick, it’s certainly not slim, but that’s a product of the water resistance. Consider that the Fifty Fathoms BOC IV is 45mm wide and 14.1mm thick but only has a 300m depth rating. Realistically, no one will go as deep as either of these watches can, but the Sea-Dweller is designed to be the more capable tool.

What isn’t so commanding in this competition is the price. At €13,900, the Rolex is nearly €10,000 less than the €23,250 Blancpain. That’s a huge difference and one that I could never justify. The Sea-Dweller 126600 feels like a more complete package and one I wouldn’t get tired of seeing on my wrist. If I really wanted something relatively similar to the Fifty Fathoms BOC IV, I’d take some of the savings and purchase a Seiko Tuna. Then again, that’s me!

Rolex Sea-Dweller ref. 126600 flat on Rolex product manual

Image: The Watch Club

Time to choose

You’ve heard from Jorg on the limited-edition Blancpain Fifty Fathoms BOC IV and from me on the Rolex Sea-Dweller 126600. Both of these two deepwater titans deserve respect, but you can only choose one in today’s showdown. Which diver gets your vote, and why? Let us know your thoughts in the comments section, and thanks for playing!

Blancpain Fifty Fathoms Tech BOC IV vs. Rolex Sea-Dweller 126600