I gave it a 3, but it's a weak 3. It was just really weird, because it's really two almost entirely unrelated books, making each part feel incomplete. First you have the parts with Quincey and Libby and their paranormal investigation. It started off way too slow, with way too much background on Quincey and just took forever to get into their "case" and to introduce Libby, at least for a book that was billed as being about "the exploits of investigators Quincey Morris and Libby Chastain." I thought both characters had potential, but they weren't well enough developed because not enough time was spent with them with so much time being spent on the second story line. I really liked Libby's good humor and fierce loyalty even more than Quincey's forced good guy personality (podner was an annoying catchphrase), but she was clearly second banana, I hope she's used more in future books. And the paranormal story was a little weak and derivative. It wasn't anything special.
And then at least half of the book, and the most compelling half, was about an FBI agent and his South African counterpart chasing down an occult serial killer. It seemed like it might eventually have something to do with Quincey and Libby's investigation, but it actually never really did. The South African cop, Van Dreenan, called Libby and left her a message on her answering machine at around page 200, and she later did a spell of him without us even seeing it, but the characters never even actually interacted. The reader knows there was a connection between the two stories but the characters never had any idea. I just don't get it at all. The story with Van Dreenan was a decent police procedural and I did enjoy it but I just don't get the point of including it in a Morris and Chaistain book, I wanted to actually read about his heroes. It really was a bizarre choice.
I really liked Gustainis' new book Hard Spell
and really recommend you try that one, and I have a feeling that the next book in this series is a lot better as well. In fact, I have a feeling that skipping this one and going right to that one might be a good choice. Although there is some background on the characters in this book, I doubt there is anything that won't be repeated in the next book and I don't think you'll be missing anything by skipping this, as much as I'm usually one for reading every book in a series. I'll try to remember to come back and edit in my comments after I read that book and note if I still agree with that opinion.