Aaron is right on.
Carbon/graphite is going to be lighter and stiffer to weight ratio. The higher the grade fiber the lighter it is per stiffness ratio.
We stop at the heavy rods in graphite because like once you go over the admiral stiffness the graphite becomes more of a broom handle where is glass rods have some give in them.
Really depends on what you are looking for in the action. More give or more of a solid backwall.
I see you are in blaine swing up one night might be easier to show this one and the benefits to each and the weaknesses of each.