At least we agree that BT r crap! Don't know about cable giving 10mb. I do know that BT should pull their finger out and get some fibre down! Wouldn't the world be a nicer place if everyone had a gigacard in the back of their machines then real streaming/the internet/telephony would come to life.
Back to f2s, I've been with them for a year plus and haven't had any problems at all. The couple of people I know that use cable, say it is slow and they have lots of lag when america wakes up and connection problems etc. F2s were a small start-up, but their service is second to none I know, when I've dealt with other adsl suppliers for my job, problems have been frequent.