I missed using one, second shot without it I connected and the bird went down in about twenty yards. I took a couple of practice shots and had good accuracy so I can't blame the tracker for my first shot being errant! There is a good video out there explaining how to set them up so they feed good on the shot. Basically you pull a ton of the string out till it starts pulling out of the spool easily before you try to shoot with it! I mounted mine to my quiver hood. Biggest COC broadhead you can tune to is my current philosophy and set your dekes up to get the Tom to strut with his butt to you and aim at his sphincter!