Could I rephrase this question?
What is the advantage of one over the other? I realize that the carbon bolt is lighter and may excellerate at a faster fps, but is it worth the extra cash???
Mostly cost! Alum bolts are less expensive. I tried alum. bolts in my Parker Safari Mag (150 lb. pull) and shot two with 125 gr. field points. They bent comming out of the cross bow,and flew like cork screws through the air towards the target!
They were 2219 shafts,so I called Parker,and a rep said not to shoot them out of the X-bow. I really like the carbon bolts better. They are either good,or junk after shooting(read no slightly bent bolts,flying off target).