RE: Accessory that everyone needs on their bow...
I might at one point put one on Nikki's Rintec. The perfect challenge would be my old Martin cheetah. I have looked at and heard others that have them though and I don't think they are as quiet as good string silencer myself. There is just no way it can hit that stop and be quiet at the same time, you will always hear it hit.
I don't doubt they stop the recoil dead though, but I bet it actually adds shock when the string hits.
It's a pretty simple device actually, I may try and just make one some day and try it out. Certainly not a new concept I have seen them for years on different factory bows.
Paul