I have shot arrows from the .006 to the .001 straightness range, and can't tell a bit of difference. Granted, like Barry said, I take at least an inch off the fletch end of the .006 arrows. Then the rest of the point end. Manufacturer once told me that's a good way to make a .006 arrow into a .003 or better arrow. He said almost all of the runout is on the very ends.