I've read that the Verizon iPhone is also GSM unlocked, but that the "unlocked" iPhone 5 that Apple sells won't work on Verizon. Is there a version of the phone that works on all networks? Virgin Mobile's (Sprint network, I think) pricing is really good, for example. Is there a phone that would work both with them and Straight Talk (AT&T)? Would I get LTE on any of the prepaid networks?