I have now seen this twice, and I can NOT emphasis enough how completely silly this is. Yes, they took the original Evil Dead movie (and some bits from the other two) and made a very goofy musical. It's raunchy, it's cheesy and it does indeed have a splatter zone in which you get splattered.
If you like singing zombies and fake blood, you should definitely see this. It's currently playing out at the Lynden fairgrounds, so you could go see tulips, have dinner and then watch the play.
http://www.evildeadtour.com/washington/buytickets/