As I recall, the spherical bushing is a Briley design, licensed to S&W's Performance Center. All S&W PC guns are first rate. I have a CQB and like it very much. It is more accurate than most other .45s that I own. Mine has been stone cold reliable with every load from Blazers to +P ammo. While it is not a compact gun, its grip is surprisingly slender and I find it quite comfortable.
I also believe that it has a locking system that is just slightly different in that it delays the opening for just a little longer time, softening the recoil.
The S&W web site has info and a diligent search on Yahoo or Google will return several articles that discuss the features in more detail. I paid $900+ for mine and have no regrets. It is a relatively slender gun for which holsters are easily found. In a good IWB holster, it can ride comfortably all day long.
IMO, this gun deserves more attention than it gets.