I have found that the number of blades makes little difference in flight on my fixed blade broadheads with my crossbow. BUT, the cutting diameter makes a huge diference. I shoot the older model 100 grain 4 bladed Muzzys that have a one inch cutting diameter. When I tried any other fixed blade heads of larger diameter my accuracy fell a good bit. Heads with 1 1/4 inch or bigger cutting diameters were worthless for me. My crossbow is slow at around 235 fps so this may attribute to the results I've had.