I used the CAE X-caliber arrows for a few years. I now shoot carbon.

The fluted aluminums are pretty light, and are flat shooting, somewhat like carbon. They are fairly easy to tune with the diameter of regular aluminums, the fletch will clear shoot-through rests easier than most carbons, especially with helical fletch. The flutes made it difficult (for me) to check the arrow for straightness with a regular arrow straightener. You will definitely need an arrow straightener due to the thin wall construction of the shafts. They bend easily, and are also somewhat more brittle than regular Easton aluminums. I was shooting into a fairly hard foam target back then, and it was tough to get 4 or 5 arrows out of a dozen that would shoot with broadheads with consistency, due to the fact that they bent easily. I always questioned whether the arrow that just shot well with the broadhead would still shoot well after I pulled it out of the target. I did use an inexpensive Pioneer arrow straightener on them and could get them pretty straight by looking down the flutes to check for bends. The day I finally decided to get something else was when I climbed up to the top of the local mountain long before daylight, and had a tough time carrying everything through a patch of laurel. I did see two nice bucks that morning, but thankfully did not get a shot, because when I got home, I found that some of my arrows, including the one I had nocked that morning, were bent, and shot nearly 6" away from where they had shot just a few days before. That' s when I decided to give carbon a try. My first year with carbons was frustrating, but I have since learned to tune better, and the present ICS carbons are somewhat easier to tune and get rest clearance with than the older, skinny, pultruded carbons.
I' m not saying that carbons are perfect arrows, but unless I was ready to go to heavy aluminums, like 2219 or something, I will stick with the carbons.