Ok, to clarify the point of the poll, one gun, one upper for the AR family. I am surprised about only 1 AR's selected in other calibers since there are a lot threads dedicated to better rounds for the AR.
Ammo would be your own consideration. Obviously in a defensive mode you will probably be able to get more ammo and weapons as a result of use of the rifle. In the country, game getting might be the prevalent use. The shotgun would be able to be used as a rifle with a rifled slug barrel if you prefer, so it qualifies. Maybe I should have posted "long gun" instead of "rifle", but then the options are wider, and limited to only 20 poll slots.
Good news is that at least one of each had been selected by 45 responses. So the variety is there, and not many choosing "other".