Recommendations please. Who is using a slip-on pad with their PC9 carbine? Leaning towards a "slip on" Pachmayr "Decelerator" model, but don't see on their website how to "size" it for a correct fit. I have a factory butt (not extendable). Would I add 1 or more of the butt "extenders" it came with.....or omit them? LOP not important to me. Best reputable online source (Pachmayr?) for ordering your recommended recoil pad? Many thanks in advance to all who respond! Any possibility of your response before am Jan. 15Th? Thanks again!