I'll never go back to AT&T plainly because of customer service. Back before PacBell bought them they were bad, got worse after PacBell purchased them. I have friends in O.C. with AT&T and they still hate them because of cust.Serv. but stick with them due to iPhone, that's going to change soon.
Odd your having problems with data in Victorville. One other thing I've done is switch my data from gsm/hspda auto to HSPDA only, forcing 4g and not giving the phone the option of a stronger gsm signal.
I've found even a weak 4g HSPDA is way faster than a strong GSM.
Of course YMMV as to any of the above comments applying to your situation.