well i know that PQ looks better via component then composite in my big tv,i did use initialy the stock composite cables of the STB for component,but quality wasn't that great,i upgraded to profigold component cables,the picture looks a bit sharper.infact when i compared the movie FIFTH ELEMENT played from xbox 1(not 360) via composite vs the same movie played in UTV world movies via component out from BIG tv.the colors from the big tv was much punchier,the movie played via xbox ,the xbox does have a very slight edge in details which can be only observed or noticed in static objects or if the actor and the camera doesn't move.
further more when i manualy streched the image in the tv when playing from big tv,the aspect ratio remained the same compared to the 16:9 DVD,no loss in edges or corners.
further more when i manualy streched the image in the tv when playing from big tv,the aspect ratio remained the same compared to the 16:9 DVD,no loss in edges or corners.