I purchased these from Barrett befor Optics Planet started caring them otherwise I would have ordered them from here. These rings are the best for large recoil rifles or anyone that may add the BORS system later, they are designed to handle the 50 BMG recoil afterall. The zero gap rings are the simplest to install: level the scope and gun, torque the gapless side down, then torque the other side. No need to verify equal gaping like other rings. I used these on a Savage 110BA with a leupold mk4 8.5-25x50 that i ordered from Optics Planet.
Pros: easy setup, light weight, strong
Cons: none
This review was written in the old system and had content requirements that are different than reviews written today.