saltflat, that is a good question with many different answers. There is so much written on differences between the two. I hate doing this, but I'd suggest doing a search. You'll find tons of info.

Personally, I have tried carbons (carbon express 3d's)(but not in the past four years or so) , but they were just too finicky with fixed broadheads for my taste. I have theories of why including inconsistant spine around the axis of the shaft, as well as shaft to shaft comparisons. Some day, I may return and take another look at carbons, but not for a while.

Below is another reason why. Most carbon manufacturers suggest checking every arrow after every shot. Sorry, but I really don't want to do that. Yea, aluminums may break occasionally, but.....