If concealability is the key and primary issue, Kahr. I have a PM9 and LOVE it, but it will never be the "tack driver" that any of my Glocks will be. I did buy a Kahr CW9 and sold it to a gunsmith as even after the 200 rnd break in it had feeding issues with any of the 4 mags i had. Soooo, got a CW40 seeing as how I'm a .40 kinda guy anyway, and it also was garbage. Soooo, my PM9 has never even hiccup'd. Not once. Soooo (don't ya hate that?) I'd say PM9 for concealability, although it's mucho clams for cost, unless you have sprayed on clothes in which case an LCP is the ticket. Otherwise, if you can hide a small brick, get a glock. IMHO, stay away from the cheap Kahrs.
Soooo, it matters not what gun you plan on carrying and hopefully not needing as long as you can trust it... After all, "any (reliable) gun will do if YOU will do".