Whats a usage cap ? (currently at 700gb downloaded god knows what uploaded this month)
Pay extra for truly unlimited/uncapped business broadband if you don't want to worry.
I've been using Onlive in the US , I'm with BT business in the UK and had no problems (registered online to my dads US address, and have a pre-payment credit card registered there too)
I have the top package you can get with BT, there have been weeks i downloaded hundreds of GB so I assume it is OK to do.