That's my point about the Kriss.
The sub gun is history beyond PDW use.
With the POSSIBLE exception of concealment, there is nothing a SMG can do that an M-4, or similar, can't do better.
MP 5, has the market sewed up as it's closed bolt and none of the others can compete with it for accuracy.
The only market for the Kriss is civilian, and they can not go there because of the MG registry being closed.
So it's a useless design. It never would have sold very well anyway.
Far simpler, LESS EXPENSIVE guns, like the Walther have failed to catch on .
I'll probably build a 9mm AR pistol, but Stuff like that generally has me looking at a 2 ft long package that gives me the same capability as a Ruger LC 9 .