Kahr
Bought a Kahr PM9 w/ Nite Sights and black slide couple of years ago, paid top $$ because they were not easy to find then. Out of the box, shot 10" hi and 8" right @ 10 yds, 8" groups, when it worked! MANY FTF/FTC failures, with all 6 mags and several different factory loads.
Back to Kahr 3 times- now it is maybe 98% reliable, still 4" hi and 3" right at 10 yds. Considering sending it to Cyl & Slide for their reliability pkg, or just going back to my J frames (640, 642, 340SS).
Since I bought it, have talked with a number of Kahr owners; seems the larger models work well, later micros seem better also. Like some of the posters above, a friend just bought the duplicate to mine, and it's 100% reliable, shoots to poa.
Slick little piece, easy to strip, easy to clean. If I only trusted it...