I do!
I have a KM Original dressage saddle originally purchased for my appendix mare.
What I loved about the saddle for me: soft seat (sitting on a cloud) narrower twist, and not too deep.
For the horse- very adjustable - the gullet bars, the billets, the thigh blocks, the wool flocking. Just fabulous.
I’ve also test ridden the S series dressage saddle. It is a deeper seat, I’d say even narrower twist - which makes me like it even more than my original- my leg can hang so nice and long - just lovely. It definitely is a closer-contact feel.
The way it sits on horses is different from the Original. The panels are straighter longitudinally- it bridged on my standardbred gelding. The head on my original also seems to be a bit higher than the S series - i can’t get that thing to sit level on my guy - though I may have to play around with different gullet bars to truly see.
All in all - I love these saddles. I wish I could make one work for my boy!