I just picked up an MPA 9mm Mini made just a bit up the road. The Mac has a history here in Georgia. A local shop has had them and I have been mildly interested. After making some trades I had some extra store credit so I pulled the trigger on one. It's not usually the kind of weapon that interests me, but I have always been somewhat intrigued by the Mac. Many will say that it's useless as a semi-auto, but I'm looking at it as a fun toy and nothing more.
I had a choice between the tradional top-cocker and a railed side-cocker. I chose the top-cocker as I really have no desire to add optics and the top-cocker is lighter in weight and in cost, being over $100 less expensive. This gun takes 32 round Sten mags which are still relatively plentiful and not all that expensive although they used to be cheaper (like everything else). The gun has a barrel threaded for 1/2x28. I'm not interested in those fake suppressors and barrel "extensions". I have an A2 muzzle break that I have opened up to .39" which allows a 9mm bullet to pass freely. How accurate this will be will depend on my drilling. I will also acquire a Lone Wolf flash hider. Other than that the gun will remain stock.
From what I understand MasterPiece Arms has brought the Mac up to the 21st Century. While the design is simple, and arguably crude, the execution and construction of this pistol is anything but crude. Just because something is simple doesn't mean that it can't be well built. From what I have heard MPA has, with the use of CNC and more modern manufacturing techniques, brought the Mac up to more contemporary standards. The gun's build quality really impresses me. The sights are nothing to write home about, but this isn't that type of gun anyway. The trigger is unexpectedly light with the expected creep. I have heard that trigger slap is less of an issue with the MPA. I have replaced the clear rubber trigger boot with a black aftermarket one.
Again, this isn't my usual type of weapon, but so far I'm glad that I aquired it.
My thought is that the 9mm might be a bit faster, at least as to accuracy, with less muzzle jump. I'll have to check out some videos to see what is realistic. 