I have one, and love it. I had the older K100 first, and upgraded when the new model was available.
The grip fits my hand well. The single action trigger is bloody awesome. The double action trigger is nice and smooth. The felt recoil is almost non-existant. The gun seems to recoil straight back. I've never had a malfunction with it. The gun is completely ambidextrous without the need to swap the mag catch.
The only thing about it I wish was better was the feel and placement of the manual safety. As a diehard 1911 fan, I wish the safety had a better ledge to ride my thumb on. However, since I never actually use the safety on this gun during 99% of my shooting, it's not a huge factor.
I have the standard model that I upgraded with the available fiber optic front sight and the Dynamic fixed rear sight, and the big button mag release. The newer C model comes with these upgrades and an Eliason adjustable rear sight. It also deletes the firing pin safety. I'd be all over this version like white on rice except I hate the Eliason sight.