I recently tried all three programs DVD X Copy, DVD Xpress and DVD Shrink. I used the movie Dirty Dancing for the test which probably wasn't the greatest of choices because it is a grainy movie anyway, but I couldn't tell the difference between all three on my ordinary 68 cm television.
Although I like DVD Shrink, ultimately I used DVD Xpress for its ease of use.
Personally I think all three programs have their place in the back up world depending on the movie you are backing up. If a movie-only is going to fit on a single disk then use XCopy of course. Xpress is good for a movie-only back up of something that's not too large. DVD shrink is simple to use if you want to back up everything and are prepared to sacrifice quality in some areas to fit it all in.
I can't speak for those with HD TV or super eyesight of course
