I have a PM9, S&W Shield, and hopefully soon the new Walther CCP but as far as carrying goes, I adore the PM9. It's all subjective and opinion, but for me the Kahr PM9 fills all of my summer carry desires:
Light, accurate, thin, and reliable. I'd also now call it fun to shoot as I've gotten used to the trigger and always seem to surprise myself with it.
Shield is a great stacked 9mm too, love the trigger in it. I had an XDs 9mm but after the recall I got rid of it. Paid a lot less for the Shield which to me is a better shooter.
Had a P239 in 9mm, but sold it after finding one in 357 Sig.. They're great IWB guns in my opinion.
I'm hoping to add the new Walther CCP to my stacked 9mm collection..looks pretty cool.
I tried a Remington R51 and it had so many malfunctions through half a box of ammo I gave up and tried the PM9 which even with a mostly polymer frame is sooo much more reliable.