Originally Posted by Ancient
There's a reason that up-converting DVDs look better over HDMI than component. It's because, legally, DVD players cannot up-convert CSS encrypted DVDs (which is just about any retail DVD you buy) over component. It's only allowed over DVI/HDMI. The only way you'll see up-conversion over component is if the DVD is made from a home movie or contains other non-CSS content.
Basically, if your TV doesn't have DVI or HDMI inputs, don't waste your money on an up-converting DVD player.
While what you are saying is correct I don't think that was the original posters question. I believe most people understand that upconversion cannot be done over component (except for a very few dvd players that were put out but I think this has been corrected). I believe the question is whether the upconversion looks any better than watching the non converted video coming from the component hookup.
There is also another thing to consider, if your tv upscales all formats to a native format, then is your tv internal scaler better than the dvd player scaler? If so then you would get better video not using the upconversion feature of a dvd player.