Need info on .300 Blackout AR pistol

[mjbskwim]

At that point I gotta wonder how much more advantageous the .300 - in subsonic form anyway - is to the .45ACP which is cheaper and easier to find. A 220 grain subsonic round vs a 230 grain round. Heavier projectile, with a larger hole.

I bring this up, because I've toyed with the idea of getting some components to convert or build a .300 blackout gun (or I was thinking about it, before the recent rash of publicized violence and fear of another ammo/gun panic)

My friend is a 300 fanatic and is where I get what little knowledge I have about it.My argument against it, has always been the ballistics are they same as the 7.62X39,which is WAY cheaper and easier to find.
His is the 300 is the perfect suppressed round.
I'm not convinced the 300bk is worth the price of admission.