Assuming the rating is on a well known boat the rating is a better gague. Just because a bot has a lot of sail area doesn't tell you much about how efficient the sail shape is, the efficiency of the hull, if the boat is a planing hull or always displacement, ect.
As a rediculious example, if you were to take the wing from an AC 72 and lay it down sideways on the hull the boat would have the exact same SA/D but be god awful slow.
As a rediculious example, if you were to take the wing from an AC 72 and lay it down sideways on the hull the boat would have the exact same SA/D but be god awful slow.
