I don't know what would be required to "crack" my iPhone (hardward? software only? can it be trusted? etc.), but I think this is the only time I'll need it internationally before AT&T will unlock it for me (and if they damage it, they replace it).

More important is for me to figure out how to buy mobile hardware / service from now on. Will it be easier if I switch to Android? If I pay full price for the hardware up front? If I use something like Google Voice or something newer and better? Or what?

I don't know, but one way or another I need to figure it out.