Someone mentioned this in a prior post :
1. It can be windsurfed, but it's slower than a windsurfer.
2. The sail isn't see through like a windsurfer and it isn't above you like a kitesurfer, so you can run into more stuff
3. The sail is handheld 100% of the time so gusts can either knock you off, or make your back hurt.
4. You get the inconvenience of an enormous windsurfing board, mounting a foil, and the inconvenience of having to pump a kite up.
5. Costs the same as a small kite.
It's pure genius.