Liquidmetal®

If for whatever reason you don't want a Rolex then take a look at the Blancpain Fifty Fathoms Bathyscaphe. It's water resistant to the usual 300m, is a more comfortable 43mm wide (and 13.40mm deep) and even includes a transparent case back, which is a feature less often found on dive watches; though, this may be due to the increased thickness they give a watches case, the perceived weakness that they give and the additional cost involved.