I have used them for two years now and love them. I use the full blade style, 100gr on an injextion arrow. 4'' wrap with 3'' flex fletch vanes. I tune them to my vanes and they fly great. Just out of curiosity I shot at 112 yards this summer and had about an 8'' group on my block so I am convinced they fly well. I shot an antelope at 55 yards last year, it looked like someone had dropped a bucket of paint. I also shot to elk with them this year, this first was in WY. No blood trail as I a hard quarter away shot, arrow went in the back of the ribs and up into a lung and heart, bull ran 60 yards and was done on his feet. Shot was again 55 yards. The second bull was in CO at 30 yards and a strong quartered to me. I slipped it just behind the shoulder blade and into his heart. He probably went 30 or 40 yards into the willows and left a mess of a trail. Im currently working but when I get back home I saved some shoulder blades to test with and see how these heads perform against them. At the end of the day.....they work for me.