It's a toss up really. They're a little more durable and don't get bent as easy. Yes you get more speed, shoot flatter etc but you loose mass and penetration power. Aluminums are cheaper. I shoot XX78, 2314s in one bow and ICS 340 Carbons in the other, both with the same head. One has a KE of 63 and one has a KE of 72. They both do the same job.