Way stiffer than Cartels
I have the C60 from a few seasons baack; aka non-EST.
Coming from the Cartels I wasn't expecting much. These are by far the stiffest bindings I've ever owned - the upgrade from Cartels is palpable. Response is fantastic, this gave me the extra confidence to b-line longer and over more difficult terrain. At the same time the comfort is improved, I find I can ride longer with these since my foot isn't flexing with the baseplate.