my 'protege' down the street has these. I DO NOT like them at all. no forgiveness when it comes to fletching clearance. they are heavy (I think he is shooting like 9-10 grains an inch) and the spin they put on the arrows, make a hell of a noise. I had him shoot a beman right after that with normal fletching and the difference in noise was unbelivable. arrow was faster too, even though it was for a bow set 10lbs heavier. I think he is now seeing the difference and I hope to have him off them soon.