There isn't any reason to get a fiberglass trunk--or hood for that matter. Yes, CF costs more than FRP, but FRP costs exponentially more to paint due to the preparation that's needed. For example, a VIS K2 costs about $800-$850 shipped. If there were a fiberglass version available, it probably would be like $650-$700. That price difference of $100-$150 would easily cover the labor costs at the bodyshop, and that's if they do the bare minimum. Since CF parts are already completely smooth and have a consistent, even surface, those just have to be lightly wet-sanded before the painting process can begin. We're talking a difference in labor time of like 15 minutes for CF versus 2-4 hours for FRP.