Im going to be using the DVI connection this week when I get my new TV (55" Mitshubishi HDTV). My cable provider (BrightHoust formerly TimeWarner) has an HDTV cable box thats comes with component (RGB, RCA, S-Video) and DVI output. From what I could tell from researching the TV Im getting is that it does in fact make a difference, as Polaris mentioned, the A/D D/A conversion when using component inputs does degrade the signal quality compared to a true Digital signal you would get thru a DVI connection. Ive only really seen the DVI input on big screens, LCDs, and I believe Plasma TVs as well. The smaller sets, under 36" that Ive researched (and to be honest, its not a whole hell of alot of them) come with RGB or lower quality inputs. I do have both the RGB and DVI cables for the big screen when it comes in this week, so I will definately take a look at the quality of both and let you know (at least one mans opinion) what I think of it.