Most guys hunt deer and most guys shoot 60 pounds or better. I am always amazed at the guys that say that they are going to stick with their fixed blade heads. JJ's testing proved that the animals die much quicker when sliced to hell and back by a a large mechanical. My experience confirms this as well. After I started using mechanicals, blood trails dropped by more than half and most deer fell within sight. I certainly can't say that for fixed blades. Yes, you could run into problems with a large mechanical using a marginal setup, but if you use the right setup there really is no debate when it comes to deer - mechanicals kill an animal quicker and a quicker death and shorter trail are of most importance in bow hunting.