Little bit of advice from a sabot shooter from back in the 80"s.
1/ stay away from Hastings products, Remington has a far better lands and grove design in their barrels.
2/ Slug guns have short barrels and on the most part Can Not burn all the powder in a 3 in slug before the slug has left the barrel, making a slug gun shoot different in every shot. 2 3/4 slugs will kill at 200 yards and are more accurate on paper as far as grouping.
3/ The larges problem with sabot shooting slug guns is that the plastic sleves on the sabots create plastic residue in the lands and groves of the barrel and tend to start and toss off groupings after every 10-12 shots and sometimes even some guns will only get 8-10 shots before the flyers start. Allways clean your barrels with a plastic residue cleaner like CVA plastic sabot cleaner, or Hopp's I believe have the same thing, for Muzzy's and black powder.
There is lots of angles in gun types here as the guys say , but more sabot barrels are sold because they can not keep a grouping because of the lack of residue cleaner in them.
I have put together a couple slug guns and now have a 12 and 20 gauge wingmasters that a proved themselves time after time in the first part of November..
Hope this helps...