well...
It won't work with a Go-Pro, as you need a narrower view lens with a larger glass area I understand.
The results on the site don't look great in terms of quality and you would need to mount the camera vertically above the helicopter - or suspend the whole rig below, clear of the landing gear - which would need to be very deep due to the depth of the lens system.
I think this would need some serious modifications to the quad, but if you were serious about 360 video, why not? 360 photos can easily be taken by stitching shots together, which will also offer much higher resolution.