My BT infinity 2 has been pretty good. A few drop outs now and again but overall pretty good.
Speed has been excellent, maybe I'm not in a congested area.
The home hub is not great I think it's causing problems with my Apple TV and the price is highish but by and large I'm happy.
Ive never used the customer service so I cannot comment on that.

I had to use the BT customer service last week (home hub playing silly beggars). The lady I spoke to (after a very short wait) was excellent, very quickly agreed that there was a problem with the router, and had a replacement despatched that day. Everything now fine again. I couldn't really have expected more.

I can't really complain about BT, but then I've never had to use customer service yet. I might change my mind if I do?

Customer service is the worst.
If only they could understand and speak English. It would save me having to repeat myself so many times.
As for the message "we are very busy today..."why don't they take more staff on.
I've have never had a day when I haven't had that message.
Having said that my BB is pretty good its the landline I have trouble with.