I used to shoot the 4 blade Muzzys. They penetration is unbelievable but I did have problems with them planing. It could have been that my bow wasn't tuned exactly right but it just seemed they were very tricky to set up. I once hit a deer at 25 yrds that jumped the string with a Muzzy 4 blade 115 gr. It went from broadside to almost facing me before the arrow got there. The arrow went in just behind the left front shoulder and came out the right side hind quarter. I could'nt believe it. The deer ony ran 20 yrds.