Motorola has pretty complete info on their boxes os their website. Full manuals, etc. I'm not sure about the logistics involved with using a foreign box on Comcast, they would have to authorize the box for use (to enable the digital channels, etc). I have a Motorola cable box (Insight HD+dual tuner DVR) and it's OK. The software is actually written by MS. It's not nearly as nice a a TIVO, but it gets the job done and so far no major glitches. Could be more resposive though (slow to respone to remote keypresses, changing chs, etc)