PN - OK up to a point...
... up to a point in time they had 24 hour support for residential users (still do for business), but sometime in recent years they cut the hours and ran only 0730 to 2200 (but it was rarely worth ringing after 2100 as they had such long queues you could still be left with "musak" playing at 2200 where a new caller would get an announcement that they were closed... and yes, I had waited a further hour before giving up, in case someone would get to the end of the queued callers... but no, no joy after 95+ minutes.
Was with them for over 15 years but they kept on doing lowest cost deals without having enough trained CS people to deal with the new customer queries, and obviously, when training new staff, that took some of the more experienced away. Then they stopped answering queries and fixing problems outlined on various web site fora - ISPreview, ThinkBroadband, etc (which had been a way to get long-standing problems dealt with, without someone needing to spend 10 minutes or longer reviewing all the comments from weeks or months with a difficult problem).
I eventually gave up when there were DNS lookups being lost, meaning that for much of the time, only 50% of site lookups were working. This meant that where a financial transaction was "going through" some of them would fail because of inevitable look-up problems leading to security issues. No, they never fixed that one.
Yes, cheap and (mostly) cheerful, but my last year or so was a constant drop in quality, month after month. Switching to FTTC was really just the start (getting 2 Mbps below the "guaranteed" 27 Mbps) and later being switched (which they argued they hadn't) unexpectedly and without notice after 6 months to a connection running at 40 Mbps (but with the DNS issues previously mentioned). I was quite OK with a damn reliable 25 Mbps that rarely had any problems, and a fixed IP, to a sub-standard 40 Mbps connection I could not trust.
Oh yes, and they did some merger/takeover but the billing system went nuts and some have had over a year without paying (yet... will see a lot of arguments, no doubt, when large bills eventually hit the carpets around the UK), and a fee of 25% added to the amount owed (so they can take 80% from the debt collection firm without PN losing a penny, but the customer will be left fuming).