Many have. You will have issue with the Browser and maybe MMS as the service books are not available for the Tour with T-Mobile.
Search Google for unlocked tour on tmobile service books and you should find a workaround.
The difference between stupidity and genius is that genius has its limits.
When you take things for granted, the things you are granted, get taken.
Even a mosquito doesn't get a pat on the back until it starts to work.
Too many people miss the silver lining because they're expecting gold.
[BES 5.0.3 / GroupWise 2012 HP2]