Been with TalkTalk 3 years now. First 2 years just telephony (Broadband was Entanet, through ADSL24)
Then took TalkTalk Plus package 15 months ago, and would happily recommend it to anyone.
OK, their phone-based Customer Service can be very hit-or-miss, but what stands TalkTalk apart from the others is their approach to forum based support. Have a look at it here:
http://www.talktalkmembers.com/forums/index.php
TalkTalk have a dedicated team of Online Community Executives (OCEs) who work on the forum during business hours. (Mon-Fri) They not only have the knowledge, but also the clout to sort out a whole range of problems that customers may have. I think they're brilliant!
Read about them here:
http://www.talktalkmembers.com/forums/showthread.php?t=247
One word of warning - don't attempt to claim that you were told (or promised) things in a phone call, if you weren't. They will access the voice call logs, and check. I've seen folks caught out!