Midnight Eyes gets a fairly good review over at Good Book Alert. Seems like the reviewer's honest opinion, which is all you can ask for.
Midnight Eyes explores these dark relatives of mainstream humanity in often disturbing detail. Accordingly, this novel is not for the faint of heart. Although the book doesn't revel in gore, a victim-mutilating serial killer is a key aspect of the book. More disturbing, and a testament to the author's characterization skills, is the mental insight and depth provided into serial killers (both the primary antagonist and already imprisoned killer near the start of the book). They are monsters, yes, but monsters with depth.