Had them for 2 years... 6 months DSL, rest with fibre.
Changing to Sky Fibre next week.
Literally the only reason I've gone to Sky is that I've got a deal with them that undercuts my current EE price by 10 quid, which EE couldn't match.
Service-wise, they've been great. Gaming is spot on, and although there's throttling of certain protocols at certain times, I'm first off the cab and less than 100yards away, so always got full pelt on their 80/20 product.
Their DSL router is a little basic, but the fibre one's decent enough, plus the fibre router let me change external DNS resolution to the Google set.
Call centre has more often than not been the one in Doxford Park, just down the road from me, so familiar accents etc.
Had one fault with them over 2 years, which was acknowledge late at night and fixed before normal business hours the next day.
Obviously mileage may vary for people, but I'd recommend them and will be back straight away should Sky not give a sweet deal next year.