I've had sky fttc 80/20 for over a year too. Apart from a local power outage I have had no downtime or congestion issues at all. Pings have always been excellent.
My only caveats are the sky hub which although pretty solid is extremely poorly featured and sky's use of a propriety version of MER which, to say the least, is unfriendly if you want to use a decent router of your choice.
Sky have now changed their T&C's to reflect the change that they no longer insist on you using the supplied sky hub but they are no help whatsoever when it comes to discovering your sky hub username/password.
A strange going on as I am sure it costs them subscribers.
