I've just read this thread - and was wondering how I can check for sure what bandwidths my Nexus S has? It was bought unlocked & I'm currently using it on 3 in the UK. We're visiting the US at the end of the week & had thought about getting a sim only deal, mostly, (if not entirely!) to use the phone as a Sat nav (not got one, and it seems pretty expensive to get one & to then get the US maps data ... ); so having used the phone at the weekend, it struck as an affordable alternative, albeit not as powerful as a proper sat nav (but, combined with using Internet cafes etc, to plan the route, mostly just for when we get lost!) However, the more I read about it, the more I realise it's not as straight forward as I thought! I've googled both the baseband version & the serial number, but neither told me the bands it uses; ( Nexus S - Wikipedia, the free encyclopedia says it's got several variants ... ) As the baseband version is I9020XXKi1 - (without an A anywhere) - is it the I9020? In which case, is it the one that's got 900 / 1700 / 2100 MHz UMTS??