I grew up in a law enforcement family and watched my dad (a city Marshall) use a 410 singleshot for 'animal control'. Back in those days, there were no Animal Control departments to call. So when feral dogs created a problem for the citizens and dad was called, he went out with the 410. I have seen him drop a wild dog at 150 feet with #4 duck shot easy. I was expecting the animal to yelp and run a ways. Nope, just did a back flip and was down - dead. Dad used #4 shot on all his in the city 'animal control' runs.
Anyways, I keep #4s in my gun most of the time because I think they would be effective at Home Defence ranges, without the danger of heavy caliber pellets hitting the neighbor's house or something.
Just my experience. May be helpful.