[Bossman]

As for the virgin sim, It's just the regular roaming they have for prepaids. I bought the sim on eBay and it picked up Tmobile USA as soon as I popped it in my phone. There is no limitation AFAIK, except that the number of countries one can roam in is less than postpaid. I use it mainly for data outside UK, and for voice calls if I am in the UK.