this is a topic that me and my friend argue about alot. The place i hunt was shotgun only and it just turned into shotgun/rifle. i prefer shotgun due the place that i hunt. where i hunt the max shot is only about 60yds.
I also like the idea that with a 12 or 20 gauge slug a well place shot is either going to bring it down where it stands or its going 20 ft and dying.
i also like the versatility of a shotgun rather than a rifle. with a shotgun you can do so much more from small game to skeet / trap.