BJ,
My observations- both the Magnus and VPA heads are good. The Stinger and Buzzcuts could be the best inexpensive heads out there. I do prefer the straight 2 blade over a head with short bleeders- especially on the Magnus as those have a stronger ferrule.
IME, when you shoot a little longer head like the Buzzcuts....the tapered design puts less pressure on the blade bevel due to mechanical advantage. The Magnus heads are thick blades and the longer taper seems to slide in easier than the short chisel point heads.
Thus, this tapered design doesn't need very expensive steel for good edge holding- its a time tested centuries old head design. I can't think of a one of either of these brands that wasn't razor sharp after going through an animal.
I have seen many of examples of the thin replaceable blade chisel and mech head blades that were dulled badly or mangled on animals....some on animals that were not recovered. In those cases I always wonder if a few more inches of penetration would have mattered????? We will never know.
I think the VPA has a little better steel due to it being carbon steel...but those can rust.
I have seen many times where the fact that this design goes through the animal so fast....its got multiple advantages to a bowhunter. I don't buy in to the ' leave the head in them with the arrow hanging out' theory....too many negatives.
Its all a trade off....but from everything I've seen, I now use a tapered COC head- either 2 or 3 blade exclusively.YMMV
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