I once posted on an upcoming product from Camelot, which is apparently a component video signal booster. Camelot has a powered s-video cable (which I had and sold, and frankly didn't see much difference in from a 30 foot run of s-video), and this product is going to be the component version of it. The schpiel I was given by Camelot was that a component signal was much more likely to degrade over a long run, and that, for a 30 foot run, I was better off using the powered s-video connection.
That wasn't true in my experience, as the addition of the component signal, albeit over a 30 foot stretch, was a significant and palpable improvement over the powered s-video. When I posted this, I think in the DVD section, Stacey Spears, one of the moderators, indicated that there was little capacity for degradation in a component video cable, even over long lengths.
My experience told me Stacy was right, Camelot wrong. But that's just my experience.