I received a half dozen Heyday black ducks as a gift. I cannot speak to the durability (only one year on them). That said, the flocking looks very realistic. Only downside for me is on a rough, cold day they road wonkily with the ice buildup.
I love innovation in decoys. I had some FUDs back in the day. That said, the ones I go back to time and again are the Dakota flocked mallards and restle-coated or burlapped divers.