My version is 4.2.1 and 03.10.01 baseband, I don't think it can be unlocked and jailbreaked.... :( Iphone 4

Hi, Thank you! I'm currently at att, thinking of switching to tmobile. I turned off the 3G on my iphone 4 to try 2G, it's not bad to use safari, but it really sucks to watch video. Then, it make no sense to have an unlimited data plan at Tmobile for so slow speed. :(

If you r using Iphone 4 in T-mobile in USA, could u pls give us your kind feedback here? The newcomers who r considering to jump out ATT highly appreciate your help!! 1. How do you feel about the internet speed under Edge (2G) comparing with 3G of ATT? How about using computer by tethering via...