This movie is great for one simple reason
A lot of horror movie stunts have been overdone again and again, such as the car not starting at a critical moment or someone getting slashed while lovemaking. This movie, however, combined both musical talent and a gory story line while having new ideas such as the chainsaw thing being unplugged and the girl being killed by the steam in the shower. It's hard now to come up with new things for horror movies because a lot of it has already been done to death (nice pun) but this movie seemed to have a few original things, which is good.
"Duh. You're the idiot. Not me."