I'd imagine the way they're built without a continuous back of the blade leading down to the main shaft, here in Washington, they'd be considered illegal since they'd be similar to a barb. Mechanicals are illegal here, too. I'd check with Fish&Game before I used one. My gut feeling is that they also aren't going to penetrate very well thanks to the frontal design. I'd also think they'd waste all the kinetic energy contained in a decently heavy hunting arrow, since I'd think they'd stop any spin instantly. there's some single-bevel heads out there that are designed to take advantage of the spin and cut more going in, sort of a spiral cut, if I understand their design correctly.