You can be competitive between 120kg - 150kg, depending on conditions. Ideal is about 135 - 140. I've sailed at 155kg at beaten the F18 fleet. (I don't know what that is in lbs sorry I don't have a weight converter on hand)
Given the predicted conditions I'd say the heavier crews will do better... the VIPER volume allows them to continue pushing in heavier conditions.
Looking froward to hearing from the guys on the ground there.
For those following along at home:
120kg - 150kg => 264lbs - 330lbs
135kg - 140kg => 297lbs - 308lbs
155kg => 342lbs
And Greg, you're a bit of a mutant (yes it's a compliment) and saying you beat the F18 fleet while sailing heavy on the Viper doesn't say all that much when we'd expect you to finish on top regardless, mutants tend to do that. Unless of course you were sailing in a fleet of mutants.