I've been using Easton A/C/C (Aluminum/Carbon/Composite) shafts for about 4 years now, and after I switched from Aluminum shafts to A/C/C's there was no turning back.
A/C/C's are light, strong, fast and tough. They will bend and break, but not nearly so easily as Aluminum shafts. I've taken almost 20 animals with them and have had complete pass-throughs on all but 2, and those 2 are the only arrows I can ever remember being damaged when shooting an animal. I've hit rocks, tree stumps and other such obstacles on the off-side of animals and my A/C/C's haven't been damaged. They will not splinter when they break, like some carbon arrows will. They also have a better straightness tolerance than most pure carbon arrows.
There is one downside to A/C/C's, and that is cost. They are expensive. I pay about $3 more per A/C/C than I did for Aluminum. Because of their toughness, though, I've bought far fewer A/C/C's than I ever did Aluminums. I would recommend trying a few and see what you think about them before buying a dozen, but be prepared to be impressed. It's worth it to have a premium quality arrow shaft. I highly recommend them. They come in 3 sizes/spines. I use the middle one, the 3-60.
Tough, light, consistently very straight, great flight