Well I've killed deer with Thunderheads, Muzzy 4 blades, Tri Locks, and Steelforce heads. Quite honestly it really all boils down to shot placement. I've had great bloodtrails from all the heads listed, and some not so great. I've had deer not even react and watch them fall, and I've had deer run like a scalded cat. Every situation is different.
I can't understand all the posts about how one head gives a better blood trial than another when no two shots on game are exactly the same, very hard to quatify and control the situation. I think that a 4 blade has the potential to give a better trail but can't really prove it.
I will say that big expandables to leave huge blood trail when they are put in the correct spot and work as advertised. I still don't use them but know a few guys that do.
Any sharp, straight shooting, well built head thru the lungs will result in a dead deer and a decent blood trial IMHO.