I've killed dozens of deer with each and see absolutely no benefit to a mechanical what so ever.First of all,by design,they're weak.They only connect to the ferrule in one place and usually with a small screw or pin.That compromises durability.With the exception of a couple design,the impede penetration.Yeas they fly like field points most of the time but any responsible bowhunter should use a well balanced and tuned bow so arrow flight should not even be an issue.Screwing on a mechanical to mask tuning problems is a recipe for disaster anyway.Using a wide cut mechanical will not kill any more deer or kill them any faster.Shot placement is the key.The last 30 deer I've killed were with a fixed blade head and only one ran out of sight.Way too mmnay people fall for the marketing hype.You don't need to throw an axe through an animal.