Thanks for the comprehensive reply. I really appreciate it.
I don't have a phone yet but I am planning to use the BYOD offering, which means that I have to choose between AT&T and T-Mobile. I am ok with either of the two since there is decent coverage of signal in my area. But, do I get any better data speeds if I go with T-mobile vs. AT&T sim? What about data caps? Does T-mobile SIM have higher cap than the AT&T one? I am planning to buy a 3G phone. I am open to either of the phones (AT&T or T-mobile). I prefer to buy an android phone. From what you are saying, if I want to use T-mobile, the phone should have 1700Mhz band; if I want to use AT&T, it should have 850/1900, correct? As long as that is the case, then the data speeds should be comparable between the two?