This is something that I would seriously consider. T-Mobile has excellent rate plans when compared to the other carriers. They have a lot of iPhone customers right now who can only access the Edge network.
http://9to5mac.com/2012/05/07/t-mob...number-of-markets-by-end-of-2012/#more-168933
http://9to5mac.com/2012/05/07/t-mob...number-of-markets-by-end-of-2012/#more-168933