The only thing the "tech" did for both Comcast and now FiOS was hand deliver the card. I installed and paired everything myself. The techs have zero experience with cablecards unless its TiVo. You shouldnt let any scrub mess with your PC.
The interal InfiniTV4 is what I have and I got it around the same time cybrsage did. I have been happy with it and their RMA support is probably the best I have ever seen. I've had my card for a long damn time now and they are doing an RMA free after the COAX dongle broke for me as we speak. If it breaks for whatever reason in the first year they will priority ship a replacement and have you send your old one back in the same box.
If you go cablecard with a windows media center setup I would HIGHLY encourage you to get MyChannelLogos, pay the small donation and love life.
I use XMBC/WMC combo with the quick switch addon and couldnt be happier.