Rolf
I have found that a 49er will sail deeper at about the same speed as an F18 downwind, but appears to stand still upwind! so an F18 will beat it on a windward leeward, but not by much!
Really, must be a very very good 49er, I'd recon that a 49er was much fater than an Inter 17 (EU spec) down wind in the light stuff, comparable at about F3 and then the Inter 17 would just run away very quickly in anything more. In F5 I would be lapping the 49ers at Grafham as I started my 4th lap and they were on their 3rd.
