I have Sky, previously had Virgin, which cost the earth (although prices have dropped since I changed) so don't know, although one of my (former) young colleagues swears by BT Vision. Mind you I think that's because he can access lots of ice hockey which he plays on a regular basis. I like Sky because I can phone anywhere anytime for up to an hour for £5 a month and with family and friends in France, Belgium, Germany, Italy, Spain, Switzerland, Norway, Portugal, USA, Chile, Venezuela and Canada that surely helps with the bills!! Mobiles and premium type numbers excluded. BT have told me several times that they can't match that. I think Sky Broadband is rubbish, but that depends on where you are.
Have you tried something like uswitch which allows you to compare?