I've got T-Mobile and am fairly happy with the service. Don't get me wrong, they suck -- but all providers do. It just depends on exactly where you are. Make sure to pick a provider that doesn't have lousy service at a place you spend a lot of time in. I think they have a 3-day return policy.

On the whole I've foudn their service to be as good or better than I had with AT&T -- and I can do international roaming with my own phone and my own phone number almost anywhere in the world.

T-Mobile will also, on request, give you the SIM unlock code for the phone after you've been with them a month or so. That way you can buy prepaid GSM SIM cards in other countries and use your phone internationally a LOT cheaper.

I agree with the above -- you can do better than the Onepass mall prices. You'll be spending a lot of money with whichever provider you choose. 8000 miles is not IMHO a reason to choose one provider over another.