I have a PM9 and its a jewel. that said, their econo guns seem to be hit or miss out of the box. many users are spending as much on ammo to break it in that they spent on the gun itself.
I agree with the "hit or miss" part, though I think that goes for the whole polymer Kahr lineup. (Their top steel-framed guns clearly get more attention in final finishing.) The PM9 seems to work pretty well overall these days, but it definitely had its issues in earlier years. I have friends that have had no trouble with theirs, and I have others that have had to send theirs back to the factory one or more times.
Based upon my experience and what I've read of the experience of others, I would stay far, far away from the P380 (if you consider a .380 at some point). Mine has made four return trips to Kahr (on their dime, sometimes after some arm-twisting) and had virtually every problem you could imagine at one time or another. They declared the frame defective twice, and they've changed every part in the gun but the stripped-down slide at least once. It's still not 100%.
The problem with Kahrs (the polymers, at least) is that they're machined for a tight fit but not to very precise tolerances. (People often seem to conflate tightness and precision in gun manufacturing for some reason, even though they're two completely different concepts.) I'm not sure there's any final finishing work at all that takes place at the factory; if there is, those people should be fired immediately, because they're stealing the company's money. Every new polymer-framed Kahr I've looked at has burrs on the slide rails, has high spots on the frame rails, and has roughly-finished polymer. Many have burrs on the barrel hood. I've seen several with poorly-cut crowns. I took a chance and bought my P380 new on Gunbroker at a very attractive price, ceding the ability to visually inspect it first, which was a dumb move. The dovetails on my slide are very sloppily milled, with the rear sight slightly canted sideways as a consequence. The barrel hood had a ridiculously large burr straight from the factory. The slide rails and frame rails had the standard burrs and high spots. The magazines seem to have been welded and crimped by someone failing their sixth-grade summer-school shop class.
Despite these issues, recent PM9 customers don't seem to have much trouble as far as I can tell. The pistols are certainly attractive from a size/weight standpoint, and they're comfortable to shoot. If you don't mind a longer trigger pull, the Kahr trigger is really nice. But if you can handle just a little more weight and height/length, you can get higher-quality pistols that are just as thin.
