So, my parents have some upgrades available on Verizon that they aren't going to use, they like their current phones, and they would be willing to let me get a 4S for the subsidized price using one of them. The one thing that I want to know before getting one is after I get Verizon to unlock it can I use it on T-Mobile or does it not work with domestic carriers? I'm good with jail breaking it if it is required, but I'd prefer not to.