Not sure what criteria you have or how you came to that conclusion, but I personally prefer AT&T. Same GSM (TDMA) /LTE tech as TM, but a much better U.S. network (both data and phone). Since I'm in the US more than I'm not, that's more important to me. In theory, ATT phones would work on any of the Int'l networks that TM works on. At least in the 35 or so countries I've been to, I've had no issues with ATT and typically I have had 3-4 networks to choose from.