My PM9 also rides in my front pocket. I use it primarily as a BUG. As a pocket gun, it has a specific function, and it has performed very well. It was expensive, but I am worth it (and besides, it is my money). If there is a smaller, lighter, more concealable, better quality 9mm (or larger caliber) autoloader available for less money, please let me know, and I will buy it.
I used to carry a S&W 340 PD Scandium J-frame (which was also expensive), but I can shoot better with the PM9, although it is 2 ounces heavier. Additionally, I believe that 9mm is a better defensive round than .38 special, and I could not shoot .357 competently in the J-frame, although I do not attribute that to any fault of the gun, and I would not suggest that there are not many shooters who could competently shoot .357 magnum from the 12 ounce revolver.
I had also heard that the recoil from .357 was so severe in the 340 PD and similar models that bullets were moving forward far enough in the cartridges on occasion to prevent the cylinders from turning and preventing the guns from firing. In response, IIRC, S&W indicated that bullets less than a specific weight should not be used.