Just a warning: I recently bought an IPhone 4S because it was unlocked. And then rather than get a SIM card (because many prepaid cards are for voice, which I didn't need, and not for data, which I did), before I lef the US I called Verizon and ordered their cheapest overseas data plan, and told them the several countries I would be in. But when I landed in Belgium, I got "no service." Their website has a chat option, and, after I went through two people (the first told me I had declined the international service, which was not true), I was told, "Oh, you are not eligible for that service, because you haven't had your phone for at least 6 months." Had I known that, I would have kept my old phone or bought a new one and stayed with AT&T. To add insult to injury, I asked how to send a complaint and was given a mailing address. I asked for an e-mail address and was told "Oh, we aren't set up to take complaints via e-mail" I feel ripped off, and it has been a drag not to be able to get data when I need it (such as maps).
So if you are looking for overseas data access, look elsewhere
