Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_0_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A405 Safari/7534.48.3) Can anyone confirm that a prepaid T-Mobile SIM (talk and text only - no data) will work in a factory unlocked iPhone 4S? I'm currently using a prepaid SIM in my software-unlocked 3GS and I'd like to upgrade it to a 4S. I have to turn 3G off to get a signal. My main concern is that the 4S lacks a toggle for 3G (there isn't one on the locked AT&T 4S anymore). Will it just default to T-Mobile's 2G network automatically? Thanks!