I had my almost new Prestige Hunter D classic reflocked with wool, to better fit my high withered TB. It had been slipping back, but it wasn't a really awful fit. Now the reflocked panels are more supportive where the hollow was behind his shoulders, and the front panel foam that was too thick was replaced with thinner wool. I noticed right away a couple different things. One, the saddle didn't slip to the left like it did - most noticable when trail riding; and the warmth of the horse transferred to the seat, how nice. I am also noticing how my butt muscles are more relaxed while riding. This, I think is odd, but, hey, I'll take it.
Overall my boy seems happier with the fit. He never did complain an iota. I feel good knowing my saddle was professional adjusted and a better fit.
I got to see the old foam - it looked new, but I see now how it cannot mold to fit the horse. Interesting.