I switched to NTL last month having got totally pi$$ed off with Freeserve.
So far there have only been a couple of times when I couldn't connect due to tech problems, but since they give you an 0800 number to call to check server status, you know whats going on rather than being kept in the dark.
It connects first time 99% of the time.
I've not been billed yet, so can't comment on that aspect.
My wife is on the phone when I'm not on line so short call are definately NOT the norm!
As for connection speeds, it is usually 45333, ocasionally 46667, but never less than 40000.
Hope that helps.