hi where are you based? the uk?
i got a dart hawk for £1700, and my brother got one for £2000, i know ppl are a bit stuck up about the dart hawk, but if you look at the results they do well in the uk, if you sail them well you will beat the new boats if you don't you wont, the hulls are as nice as anything (otherwise the ex40 wouldn't have coppied them) its only realy the self tacker and snuffer which you can add that makes much differance,
as for a hobie 18 conversion why not? right weight 180kg, right length 18', get one for £1000(with a trailer if you are lucky?), £200 for a tornado sport sale, £150 for a spinnaker and pole and bang £1350 you can take on any beach cat on the water, if you can sail that is