The civilian PDW, my Sig MPX Copperhead.

[Defaultmp3]

In general, additional points of contact for greater stability. Better platform for optics, red dots, etc. Usually higher magazine capacities and in many cases longer barrels (7.5" vs. 4").

Of course everything is a trade off, in general handguns are easier to conceal, usually faster to employ and in most cases a much lighter defensive tool.

Don't criticize a wrench because it isn't a hammer, don't criticize a hammer because it isn't a wrench.

The problem is the "in general" part. With a stock/brace that short, you're super scrunched up; I don't find that to be conducive to shooting outside of standing on a flat range with no movement, or possibly barricade work. As for being a better platform for optics, I don't see any major advantages over an optic ready handgun. If reciprocation is such a big deal, you could always get a rail mount, à la ALG 6SM or other open-gun-type options. You can't easily mount a WML on it except at the 1200, and then with as short as the handguard is, switchology will be wonky. The barrel is 3.5", not 7.5". There is no real way to attach a suppressor, given that it has an integrated flash hider. The magazine it ships with is a 20 rounder; pretty easy to fit in a larger mag for a pistol.

I'm not against small PCCs, I have a CZ Evo cut down to K length, and I think something like the MPX K is perfectly cromulent. I'm questioning the utility of super tiny PCCs like the MPX Copperhead that have given up so much to get to that size. At least with an MP9 or FLUX Raider, you can easily attach cans and have rails on more than the 1200. With the Copperhead, I'm just not seeing the juice being worth the squeeze at all; by my analysis, you're not getting any significant upsides compared to a pistol, have many downsides, all for an extremely niche application (civilian PDW use, but something like an MPX K or Rattler is too big).