For AT&T prepaid, I can verify that all of these work as normal (with a post-paid plan) except for international roaming. I haven't traveled internationally sin

For AT&T prepaid, I can verify that all of these work as normal (with a post-paid plan) except for international roaming. I haven't traveled internationally since making the switch, so I don't know about that one. That said, you can always just buy and pop in a prepaid SIM card if you're traveling for extended periods.