I have never used them, they have been around for years for 1911's. One thing you have to keep in mind is that the spring may be too long using one, and they used to have a short life when they were made out of plastic. With the modern polymers they probably last longer, personally if I went that route it would be with a Wolff spring in a stiffer weight. I have one in my Star Super A, and it has very very mild recoil even though it is pushing 115 grain bullets at 1200 fps. Get the spring kit and you will get several weights, so you can tailor to the loads.