Curac
Check the Jan/Feb Windsurf or Boards (can't remember which), as they have a review of 2 of the Severne wave sails compared to most others.
From memory one was the "classic", which was bombproof but not too high performance. They other was a sort of competition model, and they raved about it. Check out the articles - these mags are still in some newsagents or I'm sure someone you know would have a copy.