Power Exchange is a 3.5 for me.This is a really great look into the world of BDSM from a newbie and first person perspective. The narrator is Gavin. It was good to feel his anxiety and excitement about this whole new world he seemed very unaware of. That was a touch unbelievable. He's a detective in a metro police department. I had a hard time believing his complete naivete at the very beginning. The first murder scene was some sort of shock to all of the cops, and that just didn't work for me. I also had some cheating concerns from the beginning when I found out Gavin was married. It was tied up in a neat little bow rather nicely, and that was another moment of "seriously?" And then Ben is there to catch Gavin...and whoa was that fast. I've never met a therapist who would engage so quickly in a relationship with someone going through that kind of emotional upheaval. I would have liked a glimpse into Ben's thoughts/logic here. I kept expecting him to slow things down the first time they were together, and it didn't happen.Then there's the murders. I don't know that I'm super intuitive, but I had the murderer pegged from the first introduction. This was another area where I felt there were weaknesses. There seemed to be observations Gavin made and dismissed. How can he possibly be telling the reader these things AND ignoring them? That was a hard sell.Despite these few issues, I found the overall story compelling. I liked Ben and Gavin together, and I really enjoyed the book. I've already bought the next to see where their HFN leads.