I had to leave AT&T when I moved to California. It was great in the East, but it seems like they don't understand that mountains attenuate the signal -- I had literally 0 bars in my neighborhood because the tower is on the other side of a hill. Not to mention anytime you drive through a canyon, which is almost anytime you're going to the next town/suburb/valley over, which is pretty often for a lot of people in Southern California.