No commercially available slug now made will harm any modern barrel up to full choke and maybe beyond. Tight chokes usually do not work well with slugs.
Sabot slugs are for rifled barrels. Either the rifled slugs or the Brennekes will work in a smoothbore. Only range testing will determine which one will group best in YOUR barrel.
FWIW, I've Brenneked a few deer with the 20 gauge Rottweil slug. Kick is emphatic, but downrange results were short bloodtrails and quick, humane kills.