I have to say I am impresed with the Quick Spin fletchings. I refletched 3 arrows that needed it and wow my shot group got really tight like a dollar coin size. I heard they would tighten your group but wow. Now I just need to fix the other 9. If you don't use them now you need to try them, they are awesome.

It's simple really, The sooner/quicker you get your arrow spinning out of the bow the better it stabilizes an arrow. You would have accomplished the same thing with a hard helical vane/ feather/ Blazer etc... Quickspins are made to get the arrow spinning, spinning is a good thing.