David, I believe A183 Bluster still has the wooden board system for sealing the keel boxes, and she has won the East Coast Race for the last umpteen years. But you should check with Jane to find out if that’s true, and if so how well they work.
A184 Aquilo II uses neoprene flaps along the bottom of the keel boxes, which Richard described in a recent Bulletin, I think it was 2009-10. but again, you should ask him to see how well they’ve worked.
Please let us know which way you decide!
Best wishes, John