If it had to be out of my cabinet it would be my Marlin Glenfield Model 50 12ga . The biggest down fall is it is so big and heavy but it is a great gun my father had me use it for everything when I started hunting .
when I travel I always take a shotgun, hoping for an opportunity to hunt shows.
That gun is an 870 12 ga Remington pump. It has a 22 inch 3" barrel with a Poly-Choke. I also have a red dot scope in a saddle mount that takes about 4 minutes to put on, and it stays sighted in pretty good. with the barrel and scop off, it fits into a small package with 20 slugs and a box of #6 and a 5 pack of 000 buck.
I would probably go with the Moss 500, especially if you could have more than one barrell. A vent rib 22 inch with a variety of chokes, including turkey chokes and a cantilevered rifled slug barrell with scope would set you up adequately for all game from Florida to Southern Canada and from central Ohio to the atlantic ocean without being at any great disadvantage. A 18 inch cylinder bore barrel for social occasions would be nice to. Not that there is anything wrong with the 870, I own both.