Forgive Me A Cruel Chuckle...
I was tooling around on the DeSantis holster website today and saw this pic.
My mind rolled to thinking what would happen if I got a pre-ban MP5K and started open carrying it with one of these.
...of course the MP5K doesn't have a collapsing stock, but you get the picture.
I asked around and that particular sub-machine gun is actually classified as a "pistol" in Michigan and thus would be green lighted to carry with a Concealed Pistol License...or open.
Makes me wonder if you'd place yourself in harms way though. My guess is that as the gun you carry become larger in size the more fear it will instill in the LEOs who are paranoid. Some might just shoot first and ask questions later.