My test bow is putting out 70 ft/lbs of KE. I don' t know if the heads rotate in flight, but they shoot and group very well. As for penetration vs other heads of similar design, I would say the didn' t penetrate as well in my test materials. Mostly becuase of the larger carbon composit ferule, at least I think that' s why. It seems to " catch" on the harder mateials. In the steel drum and foam " cube" target penetration was as good as most other heads, so I think in game they will do just fine. I see no reason not to use the heads especialy if your a NAP fan and want to support their products.