anybody have any input on which to get??? the carbon or aluminum si hollowgram cranks? Never used the carbon before.

I have had both carbon is nice but if you can get the si alluminum ones i would go for those talk to your lbs and see if you can get them they are pricy thought at i think like 600

I think Matt18 is correct the alum version is lighter and stiffer than carbon, it's comes down to your preference if looks then goes with carbon but performance then Si alum crank all the way. Carbon version is made by FSA Taiwan and Si alum is made here in the U.S.