It wasn't my choice at the time. My phone HTC Aria is an ok phone though. I don't have service on it anyway and the SIM isn't even in it anymore. I have it rooted, but have yet to put a new ROM on it.
You should unlock it and bring it into metro or a service like criket, tracfone, etc :-P
But yes AT&T definatly is not a good service... I have had T-Mobile, Verizon, Metro, StraightTalk, AT&T and I can safely say AT&T and Metro have about the same speed and service... my prepay (straighttalk by tracfone) has better service and faster 3g then AT&T. Their 4g gets even worse!