I could see a well made, reliable box fed shotgun with a 10 round or more magazine being useful in a military-style vehicle check point. In my experience, the checkpoints are outfitted with 1-2 guys with rifles and 1 guy with a belt fed weapon. When a car and its occupants become testy at the check point the idea is to open up with the belt fed weapon.... but in a lot of these situations belt feds could be cut off doing to friendly troops being in a similiar direction on patrol or the prescence of a ton of civillians behind the testy car, or the fact I served under 44s administration. Rifles work of course, and maybe this is just my preference for shotguns, but if I'm shooting through a car window I'd really prefer buckshot and a lot of it. If the vehicle is a threat I want the driver dead, and I want all his friends dead to. If I had 10 guys with rifles on the check point it'd be a mute point, but if I have 3 guys at most, with a lot of potential for the belt fed to be cut off I want a lot of lead in a short period of time.