How does a replacement rudder with a substantially lighter core material or one with carbon fiber meet class requirements?
Other than weight savings, I can't think of a good reason to go with those options if it involves a higher cost. The only other avenue for improvement is durability and quality contruction should negate that. Foam core is more expensive - and is certainly more workable for those doing the construction - than balsa; yet balsa is great for core so long as it's kept dry.
