I have both guns, got the CK open gun, super tight fitted as in to tight. I put 6k rounds through but the slide cracked at 4K. Gun felt better with the cracked slide as it was now a bit looser fit. Send the gun back as crack got to big. Right before I sent the gun for repair to have new slide put on I ordered a Chaos. As soon as I received the chaos the fit was great ran day one and still going a year and a half later. I never shot the CK when I got it back 6 months after I sent it in and I never will.
Atlas Chais all the way for me.