I really like carbon shafts, especially Beman MFX Classics. Fletching new shafts is no problem, keep em clean and wipe down with 91% Alcohol to be sure. However, eventually shafts need to be reflected if not lost or broken. Aluminum is soooo much easier to get the old fletching off. I always used knifes or razors to get the quill and all glue off, then soak for 10 minutes in acetone, wash off and wipe with alcohol. However, I nearly always damage the carbon shaft when trying to remove the glue and quill from them. I'm going to try the dull knife on them next time -- I've always used sharp knifes or razor blades and they dig in.
The last batch I worked on (a few days ago) i soaked in Acetone for about 10 minutes and wiped them down. No problems so far but if the dull blade works I'll stay away from the acetone.