They've lasted on the market longer than I ever thought they would. I gave them a good testing, but only because I make it part of my job. Test over, got exactly what I expected, will never put one on an arrow of mine again. I prefer things designed and built on true fact and scientific study not conjecture and supposition. They'll work if you have no other option, but Blazer, Max Hunter, F-F Flash...all a much better choice in my opinion. Though I would use them in a heart beat before using the Aerovane II.