I like the idea, could be lot of fun doing this FPV.
Wish it was a little more compact so it can be used in less deep waters.
Too bad it does need a tether, can't go into the water to retreive if it failsafes or gets stuck.
One thing is very disappointing about this drone though, the camera. For the price of $6000, a 1080/30fps camera is just a serious ripoff.
And what a waste, build such an awesome drone for recording underwater, and then add such a shitty old camera.