I am now using the turbo nocks,I really like them I had to change my rest setup slightly compared to a conventional fletched arrow but I got them to tune nicely and I am keeping 1 inch groups at 40 yards and about 2-3 inch groups at 50 yards,If anyone else here has used them please let me know.I am shooting the GKF Mirage dropaway rest and I put a stiffer spring on it to allow it to drop away quicker.A dropawy rest is a must for turbo nocks.
http://www.turbonock.com