i did that and it worked for me. ziphone really does seem excellent - it can even fix some bricked phones and doesn't need itunes to be expunged first etc. etc. however, to be sure i would always read around a bit e.g. hackint0sh forums. the phone i was using has (and always has had) wifi problems. it didn't fix that so i couldn't test everything - some of what i say is from what i hear off other people. i suspect the phone in question either has hardware problems or a strangely corrupted baseband from what the person who originally unlocked it did (early anysim?) so that's no fault of ziphone.