Randy does tend to be too "hip," but I was really impressed the other evening when he complimented the one guy for singing the melody. Too many contestants forget that songs are written with specific melodies. Some embelishment is okay, but there is no need to destroy a song with spastic runs and interpretation.
Simon is, well, Simon. I find it hard to believe that so many of these contestants don't have at least one friend who will tell them they can't sing. That is why we need Simon.
Paula is my favorite because she is so much nicer to look at than Randy or Simon and I think that's as good a reason as any.