I actually bought a dozen of the 125 grain zwickey's, but I'm not smart enough to put an edge on them as sharp as I would like. So I bought a dozen 125 grain Muzzy's. Is there a special secret to sharpening those heads? I only ask because I can put an edge on a knife that would shave a buffalo? Have any of you by chance ever used the Magnus 2 bladed stinger heads? I spoke with a traditional guy today that told me they are razor sharp in the package, screw right into my legacy inserts, and fly like darts? In fact, he claims that he has had two complete pass throughs on bull elk with the same head, and that he would never consider changing? If that's true, that sounds pretty good?....Joe