I am skiing a C75 proto, apparently some subtle changes made since mine.
I skied well on it straight away, found it physically demanding so Adam suggested some setting changes which took some of the load away, went through a few fin settings before settling on boots forward to 28.5" from 27.75". Fin adjusted accordingly and now i feel like i can forget about the ski and worry more about me. I liked and skied consistently on the 3.4 Denali, especially with the cg fin in it, and not as well on the c65. I believe this ski is better than all before it and cant wait for warmer water to really feel it.
My son skis well on the c65, I guess the next step will be to put him on a 75 and see what he does!