I must say that I've had some issues with my Covert, but Karl has treated me very well and has taken a personal interest in my problem which should be corrected in a day or two. My first R9, which I regret selling to afford the Covert, functioned flawlessly out of the box. My Covert's problem was, according to Karl, one of two that they have seen (out of 6000) that had an out of spec firing pin retainer, and frankly I'm not sure whether that may have occurred during the Covert upgrade at WC.
1. Re: chatter marks in the barrel-should make no difference. This is a close range defensive weapon, not a target pistol.
2. Re: grip screws...either tighten at the range after 50 rounds and when you clean it later, or go to John's screws and don't over-tighten.
3. Re: FTF/FTF: grip tightly. Keep screws tight. Don't overheat the pistol. Keep it clean and properly lubricated. Use correct ammo and test each box before using for carry. If that doesn't work, call Maria.
Just sayin'
John