Rob said it very well. My personal opinion is that mechanicals were made to be used on deer size game. Their are some tough deep penetrating ones, but even the toughest mechanical heads that I have tested don't even come close to the strength of the mid range to top of the line fixed blade heads. Some mechanicals actually penetrate as well as a fixed blade head, but they still have "weak" points. All I can say is I never recomend them when asked, but for those who insist their are only two that penetrate well enough for me to consider.

TAKE YOUR KIDS HUNTING AND YOU WON'T BE HUNTING FOR YOUR KIDS