Wayne, like you I am primarily a deer hunter, but did some hog hunting when I lived in Florida. I shot a hog down there with the Muzzy broadheads you were talking about. The shot was 28 yards broadside and the arrow passed through the hog. She ran about 70 yards and dropped from the double lung hit. It sounds like on the two you lost you may have slipped the arrow in a little far back and not caught the lungs. No animal, hog, deer, elephant, whatever is going to go very far with both lungs deflated. The increased cutting diameter of the Hammerhead may have helped collapse both lungs on the other shots allowing you to find the hogs easier. My feeling on the subject is that a smaller diameter head will kill just as quickly as a large diameter head, but the larger head gives you greater margin for error. Obviously you are confident and successful with the Hammerheads so I would keep using them.