I am on Comcast. 6mips, XP SP2, 1gb Memory, Thomson TCM 425 modem. Linksys WRT54GS Router. have been on Comcast for over 3 years, I was using my own SB4100 then did a switch. I do not use any of Comcast's Software on my PC. Got burned a few years ago when their rollback software was deleting .dll files. That was with another system using Win 98 SP2. Sygate Firewall, AVG Virus program on present system. I do a lot of uploads to the Comcast FTP server for my 5 web sites. Also I send a large Access file a few times a day to another office using PC Anywhere.