NAP makes the Killzone which is one of the best mechs made - I shoot them. Rage +P and the hybrid Grave Digger. I still don't understand the guys who talk down about mechanicals (on every bow hunting forum they belong to) they have far superior flight characteristics than fixed and will do a ton of damage even on mediocre shot placement. The guys who use only fixed heads are the same guys who stuck with their black and white TV's when color sets came out, they also drive manual transmission cars/trucks when an auto will do just as good!
I shot one of my birds with one last year. Did the trick in short order. My arrow did pass through on a going away shot through the back.
Shot a bird last year with the Killzone. Completely wrecked that bird! (in a good way). I prefer to get them straight facing me or completely away from me. Ruin less meat that way if you get into the breast if they are broad side. Bought some of the Double Cross's this year too just in case. Although I'm pretty determined to get a decap this year. The 100g (2" blade) Bullheads are flying pretty dang good at 20 yards on a Black Eagle Outlaw w/300 spine. Although I learned really quick today if you wanna shoot the Bullhead, shoot an arrow about 3 to 4 inches longer than your normal arrows. The blades, especially on the 125g (3" blades), have a tendency to come very close to your sight and possibly your fingers. I instantly knew when I hit full draw I needed to let down very slow!