For an old revolver shooter, I found the transition to the CM-9 trigger very easy. It has a better trigger pull than any out-of-the-box S&W revolver I've ever shot.
I had a PM-9 for a while that I used for pocket carry. Overall, I liked the size of the pistol (which is its biggest selling point in my opinion) but HATED the trigger. It's a nice smooth pull, but god is it long and the reset is full. Otherwise, it was a decent little shooter and my example was 100% reliable. Only other negative was the takedown was a little challenging if you're used to Glocks, M&Ps, XDs, etc.
Just an update... we ended up with a CM9 from Point Blank in Greenwood. No chance to shoot yet, but can't wait to break it in. What a great sized little gun but still solid feeling.