If you own your phone, T-mobile smartphone plans are $20/month cheaper. That's $480 over a 24-month contract, it doesn't pay to get the subsidized phone. (Yeah, unless you get an N1, it's still a branded phone with some crapware, but they will unlock it immediately and you can change your plan at any time.)
T-mobile, in my experience, is on the right side of almost everything in this argument. Of course they probably have to be given their relative size compared to the other big players.
I gave up T-mobile a couple of years ago due to call quality issues here in Denver. I'm hoping they've fixed it.
