Having already been a fan of the FN P90, when I saw the Sons of Guns episode, I liked the ZK-22 from the get go.
I was dismayed at what appeared to be a likely prolonged time to market and then Red Jacket imploded with the collapse of the Hayden family.
After seeing that Meaux moved on and brought his design to market at Aklys Defense, I then found out about the other stock cited in this thread that more closely models the P90. I thought about that one for a moment but it doesn't make use of the P90's magazine position even though it has it present (an ammo box? really?) and the ZK-22 has the longer rail, so I went for it.
I like it, the one time I've taken it to the range so far was a blast, and it's shorter than a GSG.