The MSBS does the same as a shotgun close range but a little higher rate of fire compared to pump shotguns so the question is why use a shotgun? It is pretty pointless.
Because of the spread. A shotgun can deal massive damage without being accurate. The MSBS needs a degree of accuracy as it will not kill you unless two shots land and it will barely take you out.
I never thought the smgs were overpowered in black ops 2 buddy there was a more balanced gun range in that game I am just pointing out some fact that the assault rifles need a few weaknesses that is all