I Have that exact setup on my GPH. It works very well and is easy to use. Right now I'm using the insert with the hole in the middle, just line up the center of the target in the center of the front sight and then center it all in the rear sight. Here is a .28" 3 shot group at 75 yards that I shot the first day I had it to the range with that sightsetup. That group is as good or better than what I get with a scope on myinline rifles. In fact the only gun I own that I've bettered that group with is my 7mm with an 18x scope.