Pros: this bolt is about half the weight of the stock bolt which means less kick.
I experienced great efficiency gains. I got about 700 shot from a 47/3000 tank.
My marker seemed like it lost the noise that the qev added.This bolt also added consistancy in velocity.
Cons:The venturi is just unnecessary weight that should be removed. This bolt is priced slightly higher than the l6 which is a little better.