I have an iPhone 4S through Verizon but I want to switch to T-Mobile now. I don't mind paying an ETF to cancel Verizon to go on month-to-month with T-Mobile.
I called Verizon and had them unlock my phone "for international use", per the instruciton of a T-Mobile rep.
From what two different T-Mobile reps have told me, I can now use their SIM card in the phone and switch to T-Mobile.
According to the sales reps, there won't be any limitations to my service after the switch.
However, from much of the research I've done online, the wide consensus is that a Verizon iPhone 4S, even when unlocked by Verizon, won't support another carrier's SIM (T-Mobile in this case) in the US. It only lets you use a carrier outside the US. Furthermore, I've seen many people saying that if it did work, I would only be on the 2G data network at best. There were other drawbacks mentioned as well, such as loss of picture messaging capability, and some other things.
The T-Mobile sales reps I've spoken to have insisted that all such information isn't correct and that I will have no problem switching. One rep did mention that I might need to call Verizon when I put the SIM card in and ask for some kind of number code. Not sure what that's about.
Can anyone clear this up for me?