RE: Board/sail combo for gusty flat water sailing
I agree with the last poster - the HS is not so good in gusty conditions. Well, that is to say, it is good when its planing because it will keep going for some time in the lulls, but it is harder to get onto the plane is short gusts.
I would suggest you look at the 2007 board range and I think you could do worse than going for an iSonic 122. It will plane earlier than the HS, doesn't get stuck on short chop (less technical to sail) and because its a slalom board will take the heavy gusts with ease.
I disagree on the fin choice as I think its overplayed. In the light gusts you need something to push against and the earlier you can do this the earlier you will plane. It does add a little drag, but since (I guess) you are not a pro-sailor I don't think this matters too much. Don't get caught up in the 'whole smaller is better' idea that too many people peddle on these sites. What is better will always be what works in the conditions presented to you, plus the iSonic comes with two fins anyway so you'll always be a winner