Here is my "due diligence": http://svbreakaway.info/boat-projects.php#nt
I suspect there are tradeoffs -
a little more windage, ever slightly more weight, a little taller obstruction when stored on deck
vs.
a little drier ride, maybe more sense of security in sloppy conditions, a little more carrying capacity.
Adding 2" doesn't *seem* drastic. If others have tried it (adding a bit ot freeboard) and compared theirs with other Spindrifts, that would be nice to hear.