I shot a 220 pound buck once with an original wasp broadhead, long shot with a Schulz longbow, the green things with the little razors held in with the copper spring thing. One blade stayed outside on the hair, one stuck to a rib, the third blade broke in half and just had a little jagged thing left that went through the heart. The buck went down in 15 yards. Everything I have used since then has been better. As far as Zwickeys go, I have blasted a Delta mounted on stuffed Microflite 12s through both shoulder bones on a large buck with a 96 pound Jerry Hill and the head suffered no damage at all. I am surprised to hear that they ever fail. It is still the first broadhead I recommend to those who are just getting into this trad thing.