I had a problem with the 90 grain 4 blade Muzzy heads I tried this year. They never flew consistent enough for me and I missed a deer this year with them.........when I retrieved the arrow the head was destroyed so I dug up the hole only to find a small tree root was what cause all that damage. I switched the heads immediately and put a WASP JAK-HAMMER through the heart of a 6 pt 3 days later.

I am sure Muzzy's are great heads. For whatever reason they didn't do well with my setup. Just find the heads that work best for you and nothing else matters.