Granted, I'm not in OC (CA, that is
), but I have TMobile and I like it just fine. From my experience, it seems that TMobile is great in urban areas, and spotty in not-so-urban areas. So in Orlando it's great. In newish rural suburbs south of Orlando it's non-existant (but is starting to get better). In Central CA it was great. In SF it was great (from the airport until I hit the tunnel north of the bridge). Up in Wine Country it was spotty.
I talk to someone who (I think still) has TMobile in Anaheim every so often and coverage seems good (from what I can tell).
At least they don't seem to be evil. *shrug*