In my family we have these GSM ATT phones:
1) Sony Ericsson T616 (my 15 y/o son). Great phone, susceptible to scratches and dings as it is an open phone. Good reception, good speaker. Bluetooth compatible photo phone.
2)LG color screen 4015. (my wife and also 19 year old daughter). Both these are relatively new. So far good results, good reception.
3) LG noncolor screen, returned for poor reception and "walkie talkie like feedback after talking. OK reception and sound. (The new LG color screen is worlds beyond it.)
4) Samsung 426. Returned for poor reception, crackle in speaker. I hated it because it had only modern jingle type rings. However, my sister in law and her daughter both like theirs.
5)Motorola T721 Poor sound quality and a weird feature set. Returned because it developed a weird, epidsodic buzz that everyone could hear, but no one could diagnose.
6) My current phone, the Motorola V600. Best sounding and featured phone I've had and I've been carrying phones for more than 12 years. Photo phone which is bluetooth compatible. I am waiting on the Motorola MPX 200 replacement.
Its a money issue, the Sony and LG are good phones, so far the V600 has been a Great phone.
Bill