I have run the shapers on my EPS Sidewinder and my old 2020 ZR800. 6 inch on both. Both stock ski. All my Pol-cheese buddies run the shapers on their 850's and love them
Loved them on the ZR 800. I could put that front end anywhere I wanted. point the bars and it would go there. Steering effort was more than acceptable.
Hated them on the sidewinder. I think with the extra weight over the ski's, they just bite TOO hard for me. It wants to lift the inside ski. The steering effort can be felt even with EPS. They seem to get "stuck" in the snow in certain conditions. I could not adjust these traits out of that set up.
Maybe if you are the type of rider that likes to " hang ham" off the side of the seat in every corner, they might be for you. Those days are over for me.
I rode a T-cat with the shapers on it without EPS, brutal steering effort.