I used to shoot Microflite #12 fiberglass shafts back in the early 80's out of my heavy Howard Hill longbows. It was a very good shaft at the time. Stronger than the Easton Autumn orange aluminum shafts which I use to use. I love good wood arrows--Acme Premium Cedar, if you can still find some or Rogue River Archery tapered cedar (offered by Wapiti Archery now I believe)--however, it's Easton Axis carbon arrows hands down when it comes to serious hunting. Here's why:
They're straight or broken, period.
A skinny carbon arrow is the best penetrating.
They recover quickly and don't flex as much on contact with game.
They are durable and with the use of arrow wraps can be refletched multiple times because they don't wear out (and are tough to break), so they are economical in the long run.