I am currently living in France and my wife and I each have an iPhone 4 factory unlocked. We are moving back to the US this summer and are wondering which company we should go do if we want to keep our phones? I looked on the ATT site and did not see any option to get a plan there without having to get a phone. T-mobile with iPhone seems to be a PITA, it would not be an issue for me, but since I travel and my wife wants to tech hassle with the phone I would like to get what ever is easiest to manage for her. Thanks in advance.