5 Winchester Supreme 3" magnum buffered and plated 00 buck (15 pellets), with the same in the butt cuff. Chamber empty, hammer down, safety on. I know, I know, why put the safety on when the chamber is empty? It's just habit. When I lay a weapon down, or it leaves my hands, the safety is always on - it's a habit that I plan on sticking with. I shot a 1911 so long it took me forever to stop reaching with my thumb for the safety on my Glock.
I'm not in the city, but I'm not "out there" either, so I don't use slugs. I have them if I need them, but not with the weapon.
I have also used the 2 3/4" S&B 00 buck, and it works pretty well.