Straight Talk AT&T.Which prepaid service would you guys recommend, Straight Talk (ATT), Straight Talk (T-Mobile) or Simple Mobile? I live in midtown Manhattan so coverage is not an issue and CableWifi is easily available. But I was wondering if any of these are faster than the other. Simple Mobile is $5 cheaper and I think they use T-Mobile. Also, if I am in the boondocks where service is horrible or nonexistent, will I be left out in the cold with any of these?