What was cool about the Paradox guns was the ability to shoot shot shells as well and have one gun to do it all. Grape, buck, and slug. You had good accuracy with slugs, they were a funky design similar to some of the sabot slugs today but did not use the wad/ shoe, Since they did not have screw in chokes at the turn of the century and carrying a second set of tubes in the field is not an option they built the paradox.
Any of you with an 870. Screw in the rifled choke tube and go shoot trap. The small amount of rifling does not really interrupt the shot pattern and will stabilize a sabot for longer shots.