I've used it pretty often but only a game standing completely still and 100 yards or less. It is very effective if done right. I can't remember ever losing an animal with it.
Even that is a gamble, i had a video on my old phone of a buck my son shot, broadside, that joker almost turned completely away with one step as he pulled the trigger, caught it low behind the leg, passed through front of chest. There is some wiggle room with a broadside shoulder/lung shot if something like that happens. Animals dont stand as still as paper targets stapled to cardboard.
