whether its 2.2.1 or 3.0, just be careful that its unlocked. if its locked then u will end up using turbo sim which sometimes is not a good experience. I think the unlocking will come in June but till that u will be stuck. locked phone would cost less though.
About mesaging, its not a porblem, there are a few applications available (some are paid and some are free) that u can install in to ur iphone and will surely solve the issue.