Finally got around to watching this over the weekend. Honestly, I didn't think there would be enough material for the premise so I was expecting something that struggles to cross the 90 minute mark, but the screenwriters managed to pull it off. There are a handful of scenes that linger a bit too long, but for the most part it's a solid horror comedy starring the Foo Fighters. It's not amazing by any means, but the writing succeeded at making me laugh and the horror bits were surprisingly gory + occasionally creepy.
As for their acting, Pat is painful sometimes but aside from him, they do a surprisingly decent job. You can tell they had a blast filming this.
Unbiased review: 5.5/10, which is actually quite good as far as horror movies made by rock bands go (i.e. Kiss Meets the Phantom of the Park, Glen Danzig's Verotika, etc.).