[insert sarcasm font] It looks like an awesome product - the video is hardcore & revolutionary...if I were you, I'd buy 10!

For a start - it looks ghey beyond words...and the description is completely false - "you can even go upwind" - maybe in 25kt offshore winds, some swell, massive fin and after straining your back - you may creep a few inches upwind on a 500m tack, but nowhere near as far upwind as a bit of muscle & a paddle will get you. As for downwind - it's a redundant product...
But I'm sure you already knew that.

...oh, and did I mention that it looks ghey beyond words?