I haven't used turbonoks, but have used a similar kind of product...FOBs by Starrflight.They work really well. I didn't have to tune my broadheads at all and got impact points nearly identical to field points (even at 40+ yards). Also, with the FOBs I don't shoot groups anymore because I break too many of them (tight groups but creates a downside as they are a little expensive). As in an earlier post about the turbonoks, the FOBs also come off when the arrow goes into an animal. Starrflight claims that you will get deeper penetration as the force to pop the FOB off is less than the frictional force created by dragging vanes through an animal. Regardless, I love the way they control my arrows and that I no longer have to worry about trying to remove old vanes off of carbon arrows. Check out their website if you are interested.

http://www.starrflight.com/