I had a quick run on the prototype one a few weeks back. Only about 10mins. I didn't have to relaunch it, but it was a nice fly, managed to jump alrite on it ( I am crap at jumping kites with lower bar pressure, as I learnt on xbox2, with heavy bar pressure, but im getting there now

).
However I also found that I tended to swing under it coming down, its probably me not being used to it, but i did notice it, (because i almost sank after landing

).