I personally don't have it installed but I've seen a number of FITASC shooters with this and other recoil reducing devices. The gap between the pad and stock shouldn't cause any problems with your mount if that's what you're worried about.
I recently bought a stock with a gracoil. I have really enjoyed it. I am ordering a bumpbuster for my primary gun tomorrow. I have had the opportunity to try a hydraulic type by a couple different suppliers. I have found them to be a little better than the spring only gracoil.
I have a gracoil, I love it. Recoil is not an issue anymore. 300 targets and I dont know I even shot a gun. I recommend them, there are many others as well, do some research on all of them then decide.
Thanks to all that responded.the gracoil seems to be the best bang for the buck with the ajustable spring tention- the bump buster Im sure is a good unit if not better.the gracoil 5/16" travel. the bumpbuster has .20" of travel whitch does not seem like much but it must be.
GW22-- I have been shooting a kickeez pad for 20 years & now at 53 year of age my shoulders are wearing out-- looking for a little more relief --I already have 3 Berettas & a superX 1 auto --chasing shells suck for reloading.