Never been at all interested in kitesurfing,but this new form of it looks like real fun.It is great fun - been at it since about September last year. Built my own, on version 3 now, all have worked well. I think the only reason there aren't more around is the cost. I've never kited so much in the off season as this year.
Do they plane faster than a race board kite? How many knots do they plane in?I don't know about plane faster than a raceboard - if you were good, probably - the foils seem to clean up most of the San Fran races in the states now. I probably need about 10 -12 knots with an 8m kite - if you can get enough wind to yank you up onto the board and out of the water, that is more than enough to get you foiling - once on the foil, the apparent wind helps keep you going. It's actually more of a problem when you stop to turn around - any sort of lull, and the kite drops out the sky, and a relaunch in the lights winds is unlikely. I've had some epic long swims. One other thing that's essential is enough water depth - probably about chest deep as a minimum.
see this video for light wind potential:
Guess you need to be pretty highly skilled--or could get cut up bad from what I've heard.No - difficulty is overrated, probably a bit harder than learning normal kiting (although I'd say a year or 2 of kiting would be prerequisite), but you start progressing immediately so it's pretty encouraging to carry on. You actually have to unlearn some kiting habits. The crashes are fairly bad, but as long as it's body onto water, not so serious. The wings do have the potential to chop you though - but probably not any worse than a race board fins. You quickly learn to fall away from the foil. Like kiting, you probably set your own risk level by your equipment, the conditions you go out in etc.