billys - I have my cable box (a Motorola unit from Comcast) connected to my Samsung TV (HLN4067W) through DVI as well as coaxial and S-Video. I'm not sure how DVI would compare to component video quality, but I might be able to do some switching around of cables and get back to you.
As far as DVI performance is concerned I've been very impressed. Keep in mind that the DVI cable only carries the video signal, so you must also use audio cables to connect from the cable box to the TV and/or to your receiver.
When I try to view regular broadcast stations through the DVI connection I see some video artifacts at the top of my screen. Although the picture is otherwise sharp, the artifacts are so distracting that I just can't watch it this way.
Digital broadcast stations on Comcast (three digit stations) don't have this artifact problem and they do look a little sharper than if I used my S-video connection. Not sure how it would compare to component video but, as I mentioned, I will check it out.
If in the end you decide to try out DVI and are in need of a cable, then you should check out some of the online cable suppliers rather than going with what you might find in a BestBuy or CircuitCity (typically Monster). I've had good experience with
Blue Jeans Cable. They've recently introduced a line of DVI cables for what appears to be a reasonable price. In any event, do some shopping around for the cable.
