Been using the same old 12 ga. Rem. 1100, rifle sighted smooth bore for the last 30+ years. It shoots Rem. Sluggers very well out to 100yds. Up until two years ago, Sluggers were all I used. Tried the Brenneke KO's and the group tightened up a bit so I now use the Brenneke's.
With all that said, out to 100yds, which in this part of the country is usually the max shot, the smoothbore works as well as the rifled bbl.
The extra 50(or so) yds a rifled bbl shooting sabots would provide, IMO, is not worth going out and specifically buying the rifled bbl if you already own a smoothbore. With the right slug, it's capable of 100yd shots and that's the max distance you are hunting.
Save your $ , buy more foster slugs and enjoy more range time with what you have....
...or invest your $ in a decent black powder inline capable of 200-250yd shots and you can use it for shotgun and bp season. Of course that is if this is legal where your at.
This also gives you the excuse to buy another gun plus extends your overall hunting season
