Oh and one other thing I'd like to mention. The Hobie tiger (18ft) weighs 397 lbs. or 172.3kg. Sure it carries a heady and a kite but that's still a lot of weight for an 18ftr compared with an'A' but they are still popular.
I may have sounded a bit dark in my reply to the boats weight but after a 2 year design and build program and somewhere around $100G costs and getting no interest I'm just a tad sensitive I guess.
Sorry if I came accross a bit strongly.
Bern