I don't use RGB for SKY as my Sony RPTV has the annoying shift to the left and while the picture is sharper it's also quite a bit darker. I use the s-video to hook up SKY+ to my PC, I also use s-video for connecting my DVD player to my RPTV.
Some methods of connection to TV's produce a picture that looks "right", the fact that RGB should be the better option doesn't always mean it works out that way
