The OWC Diver Case looks like a diver case because it is a diver case. Our cases are engineered to perform as a dive watch and can (unlike many) be dismantled and reassembled easily with the correct tools. Simply put an OWC Case works better and can be fixed.
We took inspiration from the classic EPSA (Ervin Piquerez S.A.) Compressor Cases found in the likes of Jaeger-LeCoultre, Longines, Girard-Perregaux, IWC, Blancpain, Enicar, etc., now seen in OWC watches today.
We distilled the essence of a diving watch married this to Compressor Theory, removed the movement ring, added screws, a modern sapphire crystal and removed unnecessary dial text to make our MilSub. It may remind you of a classic, but it is an OWC.
OWC’s Diver Case is one of the few true Super Compressor cases currently in the market (http://www.orangewatchcompany.com/musings/compressor-principle/). It is more expensive to make, it is stronger and more resistant to water. It is just a better case.