Works just fine, most of the time - Spuhr Leveling Kit for Separate Rings

It works well for the way it is designed. I have used it a few times with good success. Very simple and easy to use. Speeds up the mounting process. The only issue I have is not with the product but with scope manufacturers. I have found that not all scope manufacturers have the base of the scope level with the reticle, and yes even higher end scopes in the $1200 range. I would have thought the scope base would always be level with the reticle, but nope; about 50/50, but they are usually close.