I have an unlocked iPhone - 1.1.1 I am using it on Rogers in Canada. I want to get a U.S. Pay as You Go T-Mobile SIM when I am in the states to use only when I'm in the U.S. Can I simply just take my Rogers SIM out and replace it with the T-Mobile one? Will this cause ANY issues to my phone or my rogers SIM when I get back? Thanks!!!