While I loved my PPK/S, there are better SD choices out there. For example, you can get a Kahr in 9mm that's basically the same size as the PPK, but is lighter and has less recoil than the blowback design of the Walther. I like the Makarov -- nice gun and cartridge and one of the best buys for the money. But it is heavy and I would be concerned about ammo availability in the future.
Again, there are nice, small 9mm guns out there that fit the same niche and are lighter and shoot a better SD round. For not much more than the Mak, look at the Kel-Tec PF9 and P11, and the new Taurus 709 Slim in 9mm -- all three about $300. At $400 you have the Kahr CW9. And for another $100-$200 there's the Kahr Pm9, S&W M&P compact, Springfield XD9sc, Glock G26 and Walther PPS. On the inexpensive end, I would choose the Taurus or Kahr over the Mak for EDC, though a Mak is fun to shoot (and I would choose any of the more expensive guns over either the PPK or Mak). If I already had a Mak, I wouldn't hesitate using it for SD, but if starting from scratch, I would go with 9mm in a more convenient package. The PF9, 709 and PM9 also offer pocket carry as a viable option, which is generally impractical with the heavier steel guns (PPK and Mak).
FYI, if you really want a .380 look at the P3AT and Bersa models for less money than the PPK. The Sig 238 is also a nice package, as is the P380 by Kahr. Don't get me wrong, I love the PPK & PPK/S and am sorry I got rid of mine -- I just think there are better choices out there as a primary carry for SD, depending on your criteria, e.g., price, size, weight, caliber, capacity, etc.. If you already had a primary EDC for SD, and were buying a secondary fun gun, and had the bucks, I'd say, "sure, get the PPK."