don't penetrate?? an 1.25oz slug (12ga) not penetrate?? i've not had a problem.
I've seen several people in my area of southern Indiana have a problem with them not penetrating both sides. Like I said, they do a lot of damage but I know three or four people that have had this happen. That's why I use the Winchesters. It's all about personal choice and what works for each person.