I had a question about Arizona GSM coverage and I would like to answer it for people who replied with the same question. Without really getting an answer, I went with someone's hunch with AT&T Wireless. Now let me tell you... on my V600, I have never gotten less than three bars unless I went inside a mall ANYWHERE I went. And in the month and a half that I had my V600, I've travelled within the Central, West, and North valley of Phoenix, North on I-17 going on to HWY 69 to Prescott Valley and Prescott, Denver, Los Vegas, and many places in Southern, Western, and Boston-area locations in Massachusetts and like I said... never less than three out of five bars unless I went inside a mall were it was 1-2 and no coverage inside a mall store (but that's expected of any carrier). With my Sony Ericsson T68i I didn't get as good coverage but I can understand that. But for you people who are looking for a good GSM carrier for Arizona, try AT&T Wireless because I've had extremely good luck with them in my time with them. If for some reason you can't get them, try T Mobile because my phones said that that network was always an option to switch-over to. Hope this helps .