An i5 from verizon comes already unlocked and can be used on any gsm network including AT&T but it won't be able to connect to AT&T LTE, just 3G and hspa+.
The unlocked verizon 4S can only be used with any gsm sim outside the US. It won't work with AT&T or any other us carrier.
I know, it gets confusing![]()
thanks a lot as now I got these basics straight. You are the man!!!