I'm in exactly the same boat - been with f2s for a long time, knowing I could get it cheaper, but staying because of the fab customer service.
As soon as I found out Opal/TalkTalk were taking over I knew what was likely to happen, and lo and behold it has been - speed has plummeted (OK, my router is old, but not THAT slow!), it takes longer to connect, random freezes, and the other night I couldn't even get a connection for half the evening.
The most annoying part is I don't think I can get anything better!
Even though I'm only a couple of miles away from a major town centre, the exchange I'm on doesn't offer any of the good quality player like Be, only BT, Virgin ADSL, Orange, Plusnet, O2 and a couple of small providers I've never heard of. We don't even have cable, or I'd be sorely tempted right now. So it looks like I'm well and truly up a certain creek without a paddle, as whatever I do will be 1) more expensive and 2) worse service
Does anyone have any ideas how to make the best of this nightmare?