I have had my eye on the Longines Hydroconquest GMT as my (almost) one-and-done watch.
Here is a watch which looks like a Rolex GMT-Master II, Tudor Black Bay 58 GMT, and Seiko 5 GMT, but is better. Here is why.
Rolex, Tudor and Seiko’s GMTs have 24-hour bezels, even though these watches are using dive cases. These are dive watches with GMT complications. Yet, without the dive timer bezel it is only a GMT watch, not strictly a dive watch. It could be argued that today since most people use dive computers dive watches are redundant. But not everyone can afford to use dive computers or need to use dive computers for casual recreational diving. So by replacing the dive bezel with a 24-hour bezel means the watch is useless for diving.
Of the three, only Seiko has both a 24-hour bezel and chapter ring, meaning theoretically the complication can now track three time zones instead of two as with the Rolex and Tudor.
The Hydroconquest GMT on the other hand does have a dive bezel for timing dives and a 24-hour chapter ring. This means you are able to use the watch for timing dives as well as tracking a second time zone.
Not many need to time more than two time zones. So Rolex and Tudor are fine. The Seiko is a time zone overkill since it can do three.
The Hydroconquest on the other hand can time dives and keep track of a second time zone. In other words, it’s a dive watch as well as being a GMT watch. Rolex, Tudor, and Seiko are only GMT watches in a dive watch package.
I am not saying I am going to dive with my watch. I like using timing bezels for exactly that — timing. But I also want to keep track of a second time zone (tracking time of family living around the world, for example). So the Hydroconquest is the only watch that does that. They thought about the design and redundancy of having two 24-hour indicators like the Seiko, and also the fact that the watch is essentially a dive watch designed to track 24-hour like the Rolex and Tudor. The watch is essential taking the best of all designs.
The point is, this watch is the only one that is truly a dive watch and a GMT watch … at luxury prices though.