Today, I installed the North American Arms Holster Grip on the 1-1/8 inch Mini Magnum revolver. I trimmed the plastic panels the grip attaches to for a better fit.
A hex key comes with the kit, but I would recommend a second hex so you can tighten the two hex head screws a little better.
Overall, I'd say the kit is very high quality. The plastic seems to be a high impact variety that can take a lot of abuse. The only weak link I can imagine is the belt clip, but it too is made of the same type of plastic. Here's a video of the install process: