Neither the Rolex Sea-Dweller nor the Submariner can be said to be “better” than the other. The Sea-Dweller has a higher water-resistance rating than the Submariner and also has a helium-escape valve; however, its larger size makes it slightly less versatile in daily life. While the Sea-Dweller and Submariner are both Rolex dive watches, they were designed for slightly different purposes and each comes with its own list of pros and cons.