Just a warning - Have just migrated to BT Infinity. Checked with the website and the sales team that the Engineer would configure one of my computers to use the new wireless router rather than the old one as I was not going to be in town and my wife is not computer savy.
The engineer installed the new modem/router, hooked-up his laptop to check and then left - leaving my family without Internet access - very poor. I phoned to complain and my wife was then given a two hour run around by various BT departments - including a technical department who did not know that an iMac does not have a separate cpu box!
Luckly I was able to talk my wife through the configuration remotly, but this is not the service I was expecting. So unless you are tech savy, make sure that the Engineer configures you computer before he leaves.
The engineer also set our laptops up (well he talked me through setting up my MacBook Pro as he didnt know how to use a mac), but it was all working before he left, and he also did a speedtest.