I won't bear witness to the "90%" recoil absorption, but whatever the exact amount is does not matter. It is obviously much less recoil. I would be willing to let my 10 year old nephew shoot it without worry of him getting "over-kicked". Honestly, I believe this is designed for tactical shotguns only. It will lengthen the distance between the eye and the sights. However, if you have a tactical shotgun then you probably have some sort of holographic or ghost-ring sights. So, the lower profile of the shotgun will be welcomed.
Pros: No gunsmith needed; Absorbs recoil rather well, faster rate of fire due to less recoil
Cons: Could have better adaptability to slings.
This review was written in the old system and had content requirements that are different than reviews written today.