I'm planning on switching to T-Mobile at some point - a family member has been using them for about a year now and no issues.
I'm still on AT&T only because I get a substantial discount on them through my employer. The day that goes away or the day I switch jobs will be the day that I switch...
Wow. A full minute fully submerged - that does inspired confidence as that would be significantly more water contact than I could see myself subjecting it to in just about any situation.