I build Hans Friedel's Raven in 14 days. I am also a very experienced builder. It is very fast and for me: tippy. I have an ear imbalance that makes balance challenging at best. His Raven is 17-ft long with a 17 inch beam. Build that and you have speed. I have paddled it on the river as well: that was an adventure. I raced it on the river, tipped once and almost went over just before the finish line. You can't have great speed and great stability with a kayak like that unless your balance is fantastic. Do whatever build you want using a "light" construction method and you get a light weight kayak with reasonable structural integrity (read strength). For a combination of speed and stability using a light build, I would suggest the Waters Dancing Solace 18EX. Not much rocker in it, 22-inch beam, 18 feet long, goes like a rocket, needs a rudder to turn because of its lack of rocker and length. If you live stateside (read not in Canada), Donnie will not ship you a kayak. If you are in Canada: no problem. The link below takes you to Hans' site.

http://www.boatdesign.net/gallery/showgallery.php?cat=500&ppuser=1809

Robert N Pruden