I've got many rifles but to me the biggest benefit of a smoothbore is it's versatility. That being it's capability to shoot both shot and roundball. I've had some smoothbores that when loaded with a ball wouldn't shoot where aimed. Old timers when faced with this problem would have to hold off target to drop the ball where they wanted it to hit or sometimes they'd put the barrel in the crotch of a tree and try and bend it enough to bring it in line. I have found it easier to sell the gun and hope the next one will "shoot center"
I have an English Fowler built for me by Jud Brennan in 1979. This gun not only throws a good turkey killin shot pattern but it also shoot a ball like a rifle. In fact, back in the day when I was shooting a lot of competition, I made many a rifleman hang his head in shame after they were beaten by "Ole Melon Buster" my 12ga smootbore.
Ole Melon Buster got it's name many years ago not long after it had been made. I carried it on a survival trek with half a doz other men. We had camped and everyone went out to try and bring in some meat for the pot. I debated whether to load my smoothbore with shot for squirrel or grouse or roundball for somethin bigger. I opted to load a RB on top of 80gr's of 2FF. I came onto a porcupine high in a tree. I steadied my gun against a tree, lined up the front bead on the head of the porky with the shadow of the tang screw and squeezed the trigger.
When I brought the headless critter back to camp, someone said, "Wow, you busted his head like a ripe melon". "Ole Melon Buster got it's name.