Giving serious thought to a water machine and the Tiger Shark is looking better and better. Just a couple questions. Are the headphone submersible? I don't plan on diving with them, but if they fall in the water, is that an issue? Can I let them float around without damage? Does anybody regret buy a certain size coil? Swimming areas are normally trashy and a smaller coil would seem better but the majority seem to pick the larger coil. Thanks for any comments.