I have been using these on a sporterized GEW 98 Mauser with a Redfield 6x18x44 Revenge and Ken Farrell base. The scope is heavy (30 oz) and this gun kicks. After about 200 heavy rounds, the scope adjustments has not moved and QR levers have not loosened. Thus far, a rock solid setup.
The trick to getting the rings on the tube is to put two drill bits or other hardened rods in the ring cap screw holes and squeeze them together slightly expanding the cap.
Pros: Very solid, stable mounts
Cons: A bit tricky to get on the scope tube but managable.
This review was written in the old system and had content requirements that are different than reviews written today.