Penetrates enough what? Im looking at things from a defense situation not a duty or assault situation. Not shooting through walls or cars. Mostly be "in the same room" distances. In which, the was will still be on the package. I've killed enough 200lb pigs with 00 that I really wouldnt worry too much about penetration.
Duty or defense your ammunition choice should be the same. Unless, you believe your attacker will be facing you belt buckle to belt buckle while standing still, in the open and nothing precious behind them.
YG posted this and it's worth a listen or two. http://www.okshooters.com/threads/ballistics-discussion.229476/