I own one with the leather flap over holster, all in pristine condition.
I bought it last year as an investment.
I do not carry it!
The cartridge has less knockdown power. I have plenty of ammo for it.
I prefer my Keltec P-11 (9mmLuger) and my Keltec P-40 (40S&W).
On both I have the extra finger tip extension on my magazines.
This addition really helps on the P-40.
My advise is to go get one, and it is very easy to install in the bottom of the respective magazine.
I also have the leather flap over holsters, alternate brown grips, and the eyelet tools which I keep nicely wrapped up for posterity. I bought them as cheap backup guns to keep stashed in handy places then discovered after I got them what a pleasure they are to shoot.
I don't give a rat's whatever when it comes to caliber comparisons preferring to carry the gun I can shoot the most accurately with my skill set. The P-40 never met that qualification for me on a consistent basis. I did extensive testing of the P-11 and the P-40. I trust the P-11 (after a fluff and buff) to not malfunction anywhere this side of 2000 rounds. Shortly after 2000 rounds the hammer assembly failed. The P-40 for me couldn't put 200 rounds downrange without a stovepipe or some other catastrophic event. Your mileage may vary.
I owned a P-40 years ago and it functioned well but the recoil was punishing. I bought a Kahr PM40 and am amazed how well it handles the recoil. I have six Makarov(s), 3 Bulgarians, 2 Russians, and 1 East German. The East German is finished out better than the others. They all function great. The 9X18mm is not that much weaker than the 9X19mm and can easily be found in hollow points. Also have a CZ83 which holds 13 rounds.
many mango seasons ago i pickup a polish p-64 for cheap. a copy of the ppk, but in 9x18. even broke down the same. all i can say it is a hand full with the fix barrel. all steel and never gives me any problems. just shoot and love the ussr steel case ammo.