Been with Sky for a while now moved from Virgin Cable. Been painless for almost 2 years now rocksolid connection 24/7, Had 2 short downtimes lasted about 5 minutes tops.
Customer support will always be the same with any big company. Big benefit is the completely unlimited broadband. There will be a day when they bring in a fup/cap though but for now it is completely unlimited.
I think the price is decent for what you get. The router is OK. I've never really had any problems with it, but I upgraded to a new Wireless N router not long after (I'm paying for speed so no point in using old wireless tech).