I've owned 2 S&W PPK's and a W.German PPK/s in .32 auto. Here's my take on these guns.
In the 1930's until around the 1980's, if you wanted a reliable small auto, these guns were one of a few options. Today, there are better alternatives.
That said, if you really want one, GET ONE. My own experience with both the German made and the S&W made were all very favorable. If you get a S&W model, make sure it is a post-2009 model. They had a safety recall on the ones made prior to 2009. If you get a NIB German made PPK or PPK/s, you'll pay a hefty premium (~$1,500).
My own opinion is that this gun is most reliable and at its best in 7,65mm. When you go to the .380 auto, recoil gets snappy and the gun MAY start to have problems. My two .380 PPK's were good, though.
Here's something you need to consider. With this pistol, as far as I know, the gun needs to be carried with the safety engaged. The safety acts not only locks up the trigger, but more importantly, it seizes the firing pin so it will not move by inertia should it be dropped. There are documented cases of PPK's carried with the safety off, dropped on the ground, and people were either injured or killed when it had an inertial discharge. These were all LEO cases that I can remember.
All that said, it is an accurate and cool little pistol. It's about 24 ounces, so it is not light weight. It is all steel, so it needs to be run pretty wet. I personally like the PPK, but I have stopped carrying them due to the safety feature being opposite of my 1911, and precluding it from being carried in my off-side pocket.