HI, simple question really, ARE most reps (like $300 plus) waterproof as advertised by the TDs? Like just for pool swimming, not scuba diving. I saw a discussion somewhere, where someone said watch needs screw down crown, then its OK, then counter argued by another member saying it's the gasket that waterproofs it, not the crown, so push ins (e.g. Cartier RM) ARE WP? Thanks. (I did try doing a search using Waterproof and did not find much info?)