I got to shoot a local manufacturers AR9 a few weeks ago and the low recoil, mvb stock, and the upper had a 6.5 inch barrel. Talking with surefire last week and they will have an adaptor for a HK MP5 mount and a AR-9mm mount early next year if testing is good to run a surefire ryder 9 on it. I have bee wanting a mp5k for a long time but cost, parts, and mag cost were the factors. Also my wife only really knows Glocks and M4s. An AR9 would be useful but I see this more of a fun and rocking a suppressed 9mm around.
This version takes Glock mags and looks like the JP but with a mvb stock to make it more of a pdw. Thoughts, I know its not optimal but...it does scratch an itch, has some kind of place, and I already have a 2 10.5 inch ARs a LWRCi and LMT so a small 9mm would be fun.
https://mvbindustries.com/product/arc-stock/ Here is the stock currently on it, I was wondering if the lwrci uciw stock would work with a blowback design.