Since Shiro actually OWNS a P9, I respect his opinion, but I also have to respectfully disagree and share MY experience...
I bought a Kahr P9 about 6 months ago, and fired about 100 rounds with no problems. Then I heard of others having problems with the slide locking back, and that the culprit was the slide lock lever. I checked, and sure enough, I had an "old" model, that didn't pivot on the post. I e-mailed Kahr, and a new one arrived in the mail about 4 days later, at no cost to me, with a letter of apology for my troubles! I received a similar e-mail response as well.
Previously, my wife's Kahr MK9 had rough edges on the grip, and Kahr custom fit a pair to a MK9 at their shop, and again sent them right out at no cost to me.
My Kahr has had NO problems whatsoever, and I ABSOLUTELY love the slim, light little carry pistol. I owned a Glock 27 previously, and while it is a GREAT pistol, it was too thick for me to carry comfortably. Check BOTH out for yourself, you may find, like many others do, that Glock works well for you.
I would hope that Shiro has patience, and gives Kahr a chance to make it right for him. From what I have read here, those that do send their P9 to Kahr always get it back functioning flawlessly. If he does not, and continues to dislike Kahrs, it is certainly within his right to do so. If I was in his shoes, I might even feel the same way. I sold a Springfield M1A after a similar loss-of-trust type experience.
PS... there's NOTHING wrong with being a research junkie! I also owned a Kahr K40 and MK40, both purchased because of my love of my wife's MK9... Sold both of them. I am VERY happy with the P9 I finally ended up with... (again purchased without EVER HAVING HANDLED one!)