Re: Glock, Kahr, XD, Walther .40 cal for CCP?
Early polymer Kahrs had dimensional problems because of what they described as 'unpredictable shrinkage' that occurred as they cured. I think old problems keep getting dredged up, usually by people who don't own one and are looking to knock someone else's taste in guns. Glock had considerable experience with injection molding before they started building guns, an advantage Kahr did not enjoy. As OT-Medic noted, the steel Kahrs have been as reliable as a brick since day one, but it took the plastic ones a while to catch up. It's been several years but they also told me the PMs tend to fair better with ammunition using heavier bullets, and more than a few people think you make the best of a short barreled pistol by shooting lighter bullets.
I bought a PM40 in the early oughties that became problematic, randomly FTFing or FTEing, but only when hot <span style="text-decoration: underline">and</span> dirty <span style="text-decoration: underline">and</span> near the end of the magazine. It made one trip back to the factory and has run flawlessly ever since. I remain convinced there's so little metal in the slide of the smallest Kahrs that they're prone to heat-related malfunctions if you treat them like a range gun, moreso the .40s than the niners. But I only ever carry 12 rounds when I'm CCWing it (5+1 & a spare 6-rd mag), and I know from years of testing that 12 isn't enough to cause any heat-related problems.
Comparing the width of a subcompact Glock, a PM Kahr and a T-series Kahr
What drew me to the PM40 is that it was the tiniest .40 S&W made. For bonus points, it weighs 20.3 ounces, loaded 5+1.
Comparing the size of a P3AT and a PM40, almost twice life sized
I'm also very impressed with the XDs. They were born from fire and have an excellent pedigree. My ace running buddy has a couple he can't break, and this guy can tear the horn off an anvil. We always try each other's guns when we go shooting together and if I weren't already so heavily invested in Glocks, I'd be sorely tempted to switch to Springfields.
But they don't match the PMs for concealability. For that, IMHO, the PM40 has no equal.
EDIT:
The Kahrs also taught me that I prefer their vertical 2-dot sights over horizontal 3-dot sights. For me, sight alignment with the vertical 2-dots is much more instinctive. So I ended up switching everything I have that they're made for to XS Big Dot sights.