Thats the worst way to do it. You need a judging panel at each one. If you use crowd participation only in the heats you'll be opening yourself up for a lot of critisim. e.g One contestant may have awesome track selection/skills and not turn up with many supporters and gets beaten by someone who is average but has 20 mates come along and dance during their set then leave. It should only be 30% of the total score in my mind Thats just my 2 cents