I use the quick release rings to share one nice scope among several different weapons. It'd be great if I had the money to dedicate a nice scope to each weapon, but I don't, and this is a lot better than buying cheap scopes for each weapon. Changeover time is under a minute and I made a laminated card with the scope adjustments in elevation and windage for each weapon. The Leupold QRW rings are repeatable to less than one MOA when replaced on the same weapon. I use the same Picatinny rail slots each time, and I bias the scope forward as I'm tightening the levers. The QRW rings are also great for weapons where the optics must be removed to clean the gun, for example, a Kel-Tec SU-16 with the gas tube above the barrel.
Pros: Leupold Quality, Quick and Easy To Use, Reasonable Price
This review was written in the old system and had content requirements that are different than reviews written today.