I shoot with2 setsof the simms modules and a small dampner on the end. this has worked great on 2 bows an ulta mag and pro 40 freedom. I am going to put the extension it comes with to try and get a little more lenght on it and see how that works.
When I first got the ultra mag I had a 4inch doinker on it, once I swithed to the simms accuracy improved drastically