It has nothing to do with if the .410 can perform or not, it has everything to do with will you (or whoever chooses one) will practice enough with it to hit with those loads. The OP is recomending the .410 to inexperienced shotgunners to me thats a pretty big stretch.
And if anyone is contacting the FBI for being a "Ballistics savant" it should be you so they can start arming their agents with .410's. Don't try to snark the snarker.
John A. Monroe, Never Forgive, Never Forget, Blood Pays Blood