re: Waterfowl shotguns

All depends on what gun fits you. Sometimes you can shoot a M2 and not a A400, or a SX3 may fit you better. Try to shoot them all and see what you can naturally hit more targets with.

I shot an over and under at ducks for years and don't think they stack up. Unless you are hunting a big comfy blinds with lots of hunters where that 3rd shell doesn't matter. I also would not get hung up on the 3.5" gun unless you are a big goose hunter.