Fred Bear used Zwickeys before head made his own Bear head. Bear also had Zwickey make him heads back in the day. I stumbled on to one of the Zwickey for Bear heads that my dad had in his collection of heads.
With that being said I use Zwickey two blade. They are easy to sharpen and round the point off getting rid of the sharp tip.
Also any 4 bladed heads that I have, I grind the bleeders off. Two blade is much easier to sharpen.
Thats of course when I am not using stone heads.!!!