I would expect a carbon mast to hold up quite well in the sun as long as you clean it and wax it every season. What you have to watch out for is scratches etc. which all mast are prone to get. Put non skid below the mast tang and where the diamond wires attach at the base of the mast.



Be a little careful before drilling holes in a carbon mast and reshooting rivits. Use the correct rivits and prep properly.



Don't capsize in the surf and enjoy the benefits of a carbon mast.