We have used both in the past, the Magnus head used to be harder than the Zwickey that may have changed since then. The Magnus comes a bit sharper out of the pack and can be easily whipped into hunting sharpness with just a carbide sharpener, provided the angles match. It is possible that you may be getting something off on the Zwickey, I have found with the people that I help get into this that when it comes time to get a broadhead that has been shot into a target a few times for practice, that the Zwickey is easier for them to get back to shaving sharp versus the Magnus after it they have been used for target practice. It think what you are dealing with is initial sharpness and a bevel angle that suits your method. Either way, they both work about as well on game.