The S5's water resistance can be entirely annoying at times. Not only do you have to open the cover to the charging port every time you want to charge (and close it when you are done), but some times for whatever reason, it doesn't think you have closed it well and you have to keep trying to seal it to stop the phone from pestering you about the damn door.
Same with the back battery cover, although I remove that less.
If Apple uses a company like Waterfi, then I am all for it (no doors/covers). But otherwise, it is more of a hassle than it is worth.