I don't see many movies in the theatre, but it was absolutely necessary that I see this in the Arclight Cinerama Dome on a Saturday night with my best friend and a crowd full of scared, giggly people.
It was so scary and suspenseful and realistic! It reminded me of The Blair Witch Project. Also, if I wake up to pee in the middle of the night, I'm going to be so scared. Also, if I hear the neighbors above me stomping around, I'm gonna assume it's something scary that wants to steal my soul and crawl inside my vagina or something.
I recommend seeing this in theatres, when you're feeling silly and like you need an adrenaline rush. It's great fun, and it's also really good quality.