Just to add to this, when you're doing a speedtest.net ... er ... test, don't just assume the server closest to you is the correct server to test with. I've had results ranging from 10mbit all the way up to 50mbit from various servers on the speedtest.net site, although they are all usually pretty consistent. So chances are, you'll have to try a few different servers and work out exactly which one is best for you. I live way down south, but I find that London and Milton Keynes (might be Manchester? London and one other anyway) are the only servers to give me 50mbit results; any others I test with usually max out at 30mbit or less!