First, don't be one of the big mech head guys claiming you always get pass throughs....they don't. I shot big mechs for years in an 80# bow. I helped test the Barry invented head, the pre cursor to what the rage is now. I know mech heads.
Mech heads work..... but they get less pass throughs than a tapered fixed head. Thats a fact. One of my criteria is a pass through- it's a devastating wound and puts them down faster.
After going all around on the different head designs, the best results I've had were from the 2 or 3 blade leading edge blade heads. They penetrate effortlessly with very little animal reaction and most animals die in sight.
A 2 blade head never has a blade pop out in from the quiver or in flight and cause a miss. I can shoot my 2 blades in practice, touch up easily and in the quiver knowing EXACTLY where it flies- no guessing.
These penetrate on shots that the mech heads stop...and sometimes that extra penetration gets me to vital organs. The taper puts less pressure on the edge...maintaining sharpness through the animal. I've had the short chisel heads chop hair and hide on the way in....not good to shoot critters with dull blades.
With a very efficient head, I don't need to shoot a high energy Bow. The 46# recurve I shot for a 2 year period had 10 or 12 pass throughs with 2 blades...big hogs...even a 700# moose.....2 through the moose as it just stood there not knowing anything was wrong. Neither of those arrows through the moose looked like they even slowed down. Moose down in 6 steps.
The 2 non pass were from qtr away shots in the off side shoulder...one was a Coues deer that shattered that shoulder.