Component's technically capable of High Definition. It's what people in America have been using to connect their HDTV boxes for years. But that's coming to an end over security paranoia so you won't get upscaled HD pictures out of any DVD player over Component (except for a few unknown brands as well as a Samsung one that can be hacked to output HD over Component).
It won't be a million times clearer than RGB SCART but the motion will be a lot more natural looking and it'll give a little increase in clarity. Particularly if you're watching PAL DVDs because most LCD TVs still don't have proper handling for Interlaced PAL movies (2:2 Pulldown). If you see hints of jagged lines when things move over RGB SCART, a Progressive Scan player will stop that.