Great job and super post, Bood Trail.
To the OP:
If you are a volume slug shooter or just enjoy quality molds,Mihec makes a wonderful Lyman 525 "pellet" clone.
You get a big pile of quality slugs in no time while enjoying every drop.
I also use both Mihec 12 round ball molds, wad and full bore. My most accurate 75 meter loads are Mihec full bore RB.
I do have half a dozen Svarog / AS molds (12 and 20 gauge) with varying success - non fitting proprietary wads from Svarog got me irritated, they are very good at blaming the customer.
And about half a dozen Lee molds as well, I like their 20 gauge RB:s. And the Lyman single trad 525 12 gauge.
If I was hunting with slugs I'd prefer Zveroboy or Grizzly I guess. Screw on wads are just a bit too much work for range practise - and after a few years, I still have problems gettying the wads centered and straight.
Round Balls and Lyman 525 pellets work nice in cups up to 40 meters, smoothbore. I sometimes re-fill factory trap ammo with those slugs for low recoil practise. But for both accuracy and power, a 12 gauge Mihec full bore Round Ball @ 1500 fps from a rifled 870 barrel is my choice for now. Easy to cast and load, too.