im on NTL 600k BB but can receive BT BB aswell if i wanted. I chose NTL coz of price and speed. I do however have the feeling that price is not everything and reliability is more important, its a case of you get what you pay for. i know of some compnaies offering BB at silly prices but will they be here in 6 mths time?
if you are in a cabled area then check them out before waiting for freeserve. if not, tough but do some homework on other cheap providers