Say what you will about Wharram catamarans, but show me another multihull design with the proven seaworthiness of his Tiki range. Nothing comes close to the number of ocean passages successfully completed in these simple boats. Even the Tiki 21, which James Wharram never intended as an offshore voyager, has circumnavigated. And the same boat, again sailed by Rory McDougall, just completed a double trans-Atlantic this summer, the first leg over as part of the Jester Challenge, and return to England just for the hell of it and to take the boat back home.
Needless to say, the larger Tikis are simply as seaworthy or more so than the Tiki 21. Many Tiki 26's have crossed the Atlantic, as have Tiki 30's and of course the larger Tiki 38, Tiki 46 and so on. These passages were not stunts, nor were they completed because of "luck." People who build and sail these designs tend to be out there living the voyaging life and going wherever they please, rather than debating the merits of boat design on Internet forums.
I have sailed the Boatsmith Tiki 30, including a delivery trip to Nassau last summer. David has raised the bar on these designs without a doubt, showing what's possible when a great design is built to exacting standards by professionals using state orf the art materials and technologies. Sure there are some ratty home-built Wharrams out there. Many people who build these boats have no idea what they're getting into and lack the skill and the funds to build them to a high standard. Yet, the designs are so forgiving they still manage to build them and often sail them far.
As for the overall appeal of the designs, as Wharram himself said, you either love them or hate them. I happen to love them because I know what they can do and I think they look really cool anchored in a tropical lagoon or pulled up on the beach somewhere.