The quick spins do slow down an arrow. They cause spinning by causing a disturbance in the air, a negative pressure on one side of the vane just like an air foil or aircraft wing which causes the lift on one side of the vane hence the spin. The Blazer is more efficient by cutting the air. Quick Spins are pretty polular and apparently pretty accurate. Give us all a report on how you like the two different vanes I sent you.