As I understand it , T-Mobile in the US uses 1900mhz exclusively, and you need 850mhz on your phone to be able to roam on other networks when t-mo service is unavailable. So, it would work on T-Mobile with no roaming coverage, and if it's unlocked you will have to reprovision the data settings before you can use text messaging or internet. There's a link posted in our T-Mobile forum for the site to help you reprovision a phone's data settings.

OK. I got a Sidekick 3 and i wanna get the unlocked Rokr E6. Now the problem is that they say your phone's network band has to be the same as the Rokr E6. Now the SK3 Network band is 850 MHz;1800 MHz;1900 MHz. The Rokr's band is GSM 900 / GSM 1800 / GSM 1900. Will i be able to use my SIMS card on the Rokr E6?