Ive had Tmobile for a few years. When i get a chance I will go back to ATT. Tmobile sold all their towers back in 2012 after their merger with ATT was shutdown.
As a truck driver, ive been all over and can tell you that Tmobile is just fine sitting still. But for me, constantly on the move, Tmobile is a pain.
If your on the phone, hands free ofcourse, and your call gets swapped from the tower behind you to the tower in front of you, its all good if that tower in front of you is the same provider that was on the tower behind you. If its a different provider, your call is immediately dropped.
This happens to me 30 times a day. It is so annoying.