I had the same problem and now that my contract is almost up, I'll be looking to change ISP. Been having a look on this site
http://www.moneysupermarket.com/broadband/ to get a rough idea of what to go for but still a bit indecisive as I need something cheap!
I know this is off topic, but does anyone else agree that this BT21CN is a waste of time and money, if they had any sense they would look to upgrade the lines to something that won't be old fashioned by the time it's done! Great 24Mbit/s broadband by 2011! Whoop-e-doo! We are so far behind and i think that £10 Billion that it's costing them should be perhaps doubled to create something more efficient! Anyone agree???
Oh yeah forgot to mention "UP TO" 24Mbit/s!!!!!!!!