Well the smooth bore slub barrel won't have a choke so there won't be any slug deformation that happens when a slug is squeezed through a choke. Also the rifle sights give you a more accurate sight picture than the bead. That's the main difference in the two barrels.
As for rifled vs smooth bore slug guns, I have both. I have a couple rifled slug guns in 12 and 20 gauge and they're for my long range slugging with high velocity expensive sabots. The new 1900fps 20 gauge slugs mirror the old 45-70 for performance and trajectory, 150 yard shots very possible, but run $2+ a slug. I have the smooth bore slug guns, both 12's, as brush sluggers. I grab one of them when I'm stalking through the timber, in a deer stand over a creek and a bunch of thick stuff, or on a deer drive. The cheap rifled slugs make a big hole and busts through small branches and such. But they only have a range of around 100 yards. After 100 yards the trajectory drops off quickly. Depending on the shotgun you might want to hold the range to 100 yards, or 75, or 50, depending on the accuracy of the shotgun and more importantly the sights on the smoothbore. It's hard to shoot accurately with just a bead on the end of the barrel. But you can get a box of 15 slugs for around or under $6.
So do you want a 150 yards $2+ a shot slug gun with scope to use all of it's capabilities, or do you want 100 yard range (depending on sights), 40 cents a shot slug gun?
Like I said, I have multiples of each, and use atleast one rifled and one smooth bore each shotgun season determined by how and where I'm hunting. I don't carry my 11lb scoped full rifled tree stand shotgun on drives... But I also don't rope either of my smoothbores up a tree overlooking 1/2 mile of bean field.
later,
scruffy
