In the main, people only post on forums when they have problems so you will get a skewed view by asking on here.
Hi @Lollypop, I moved to BT just over a year ago after many years with Sky. I'm very happy with BT as a broadband supplier, my speed is good and consistant, but it was with Sky. I'm not that knowledgable on the subject but my impression is that it's more to do with how far you are from the cabinet, how many are connected etc than the supplier itself. From my experience, I would say that if you have had good consistant speed from Sky then you are likely to get similar from BT.
Customer service in the unlikely event that something goes wrong, is another subject. I've not had any major problems with BT myself but getting hold of someone at BT with the necessary knowledge seems to be a lot more difficult with BT than Sky, that's my limited experience. Avoid 'Live Chat' with BT and phone, keep trying until you get a UK call centre.
I've been with BT for quite a few years now & personally I've never had any broadband (fibre) or phone issues.
The TV side is a different ballgame though. The recording box (Youview) gets frequent updates , some which are not always wholly welcomed and without having a router than can block specific URLs you can't prevent these from happening.
Like most their customer support can be a bit iffy , some of it is overseas , but the BT employees who monitor this forum are excellent at resolving issues if they can't be solved via the usual route.
I agree with @licquorice, there are very few people on here, gurus etc. excluded that post saying how happy they are with their service. The vast majority of posters do have problems but they are a tiny minority compared with the number of total BT customers.
Happy BT customer here. Had a problem when i joined but the engineer was around next day and the problem was fixed. I do live right by a cabinet so get pretty much full speed and realise i'm fortunate there. Found other isp's a lot less willing to send out engineers when needed.