With you on this.
When I moved my A&A ADSL2+ service to a 40/10 FTTC service a few years ago now (moving house), it was painless. I even got a fault on the line during installation of some new flooring (I suspect first BT engineer install guy put a staple through the cable, and then when the flooring people were doing their skirting board stuff to hide the cable behind it, something got knocked). Anyway, the fault was fixed that same day.
I later realised why it was so quick - A&A by default provision business lines for their broadband (certainly for unit based packages, not sure about Home::1 - would need to check that) which means you always get super quick fault response/resolution as BT treat the line as a business line.
I had to move to Zen due to the peak-time usage issue. If I have a fault now, it will be the standard care level where it may take a couple of days for them to come out and fix.
I would move back to A&A if they offered some kind of unlimited package, but that peak-time usage is a killer.
Edited by deleted (Thu 23-Apr-15 14:14:00)