Thanks, all! I actually put my question rather badly. I was interested if there was any issue with the hardware NTL supply their customers, in particular their cable-modems.
Virtual Snorker rightly pinpointed what I wanted to ask and never asked...

There are always some problems with winmodems on a copper line under Linux, so that was the reason I was asking.
Looks like I can use the NTL cable modem under Linux. I am running SUSE 10 which is rather choosy about modems on copper BB and doesn't like quite a lot of them.
Thanks, again.