I got switched over from o2 in the week following a week's delay at my request to sort out my networking. I've eschewed the supplied router having recently acquired an Asus N66U Dark Knight.
Since I've had historical issues with line noise and, in more recent years, weird SNR jumps and disconnections I was a little nervous but having tested across the last few days things are looking pretty good. My fibre estimate was 57Mb and these tests tonight are pretty typical of what I've been seeing.
Certainly can't argue with that @ 450m+ line length! CS has been helpful too. Long may it continue.