Thanks Dan... great info. I am not sure what a "box rule" means, but i do know that the class is very standardized and all the various boats have to meet the same lenght, width, mast height, weights, materials... and much (much)more ....
I was actually compairing the F18 standards to the Mystere info i found online at the International Small Catamaran Handicap Rating System (SCHRS) website... and it seemed VERY close.
This all came about from reading the post about the 104 class and wanted to learn more about classes... really cool info...