For a cruiser/racer, not new and presumably not state of the art in design why would you go to the expense of CF rig ? Or in fact are you thinking of buying a brand new boat ?
Sorry that is not answering your question is it ? Reality is I have no idea (about a lot of stuff in general) but carbon rigs in particular except that a lot of owners with seemingly more money than sense have them.
"Do you think God gets stoned? I think so... Look at the platypus." Robin Williams.