If I may something about the audio.......to me audio is key but not essential in the digital world of animation. This is due to the fact that you can overlay anything to your animation. If I was watching a demo reel.....I would grade for one Quality, as Danny said if the first 30secs don't grab me...I go onto the next reel.

I would watch them in this manner:

I would play the first 30 seconds and decide on if I want to continue. If I do decide that this is worthy of my time....I would rewind it and play the music.....just to see the mood that develops. The one thing I have learned from giving advice to my artist friends is that my own personal tastes do not play a part in it.....I have to give good opinions and why.....not just 'I don't like it because I hate yellow'.

The music should fit the scene.....try out several tracks. To give an example look at the movie 'The Matrix'....notice when the bullets are moving in slow motion.....so does the sound....it's not crazy techno at 190bpm.

Anyway as you can see for me to grade something, everything about the reel has to function as one unit....and of course be top quality