Took my MK9 to the range today (total of about 4K rounds through it).  Gun funtioned without a problem and shot well.   When I got home I inspected it and cleaned it as per usual.  To my surprise and dismay I found a stress fracture/crack running vertically from the exterior surface of the slide barrel opening to the opening for the spring mechanism.  Not a through and through crack - YET.   I have not shot much + P through the gun - likely less than 200 rounds as I found the recoil bite more than I cared for.  I have sent an email  to Kahr. will wait and see what they offer/say, but at this level of use this is clearly a manufacturing or metallurgy defect.  

I'm interested to hear your results. Kahr should do right by you. Let's see.

I was going to wait until the issue was over to post again, but since two have asked...

I recieved a prompt email reply with auth number to return the slide for replacement; after a few more emails to assure myself that my trijicon sights would not be tossed wout with the old slide and they would be installed on the new slide, I sent the slide out via the cheapest UPS route possible (cost was about 14 bucks).  Kahr now has the slide as of Fri  9/3/04.  Now it is " hurry up and wait".

 Slide returned in a few days - didn't get around to the slide and frame for a few more days.  Slide would not seat on frame - it was hanging up and would not engage on the rails.  Called kahr and now they have the new slide and the frame.  Again in hurry up and wait mode.  Folks at Kahr were nice and pleasant on the phone - no hassles, but still no functioning firearm.