When I tried them, I had a 50% failure to open rate. I shot 6 deer with them the year I used them, recovered 5. Two of those had a hole that showed the blades didn't open and when I recovered the arrow from the lost deer, blades were closed with no sign of opening (hair or blood between blade and ferrule, nicking of blades). It may have just been me though because I figured out that you have to manually open the blades and then reclose them before your hunt to make sure they weren't sticking. That and I was shooting a bow that shooting about 270 fps and that may not have been fast enough

Who knows.
Good luck with them, I'm hope they do work well for you.
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That look on my face is not concern, its shock at your utter stupidity!
Check out Redneckarcher.com. It's an adult archer/hunting site that feels like hunt camp.