I think that what was decided in a discussion on sailinganarchy was that in straight line speed the moth would take it, but the tornado would win around the course.

Also the depth of skill is much high in the tornado class than the moth so your average moth sailor should not beat the average tornado.

But the T hasn't gotten faster in a long time, granted they did get a new rig and everything but the moth is developing very quickly, in another ten years it would not surprise me to see the moths beating everything on the water.