Hi Tonio, I have used all the wings, during R&D and also recently during own personal sessions. Often on these smaller wings the range depends a lot more on your skill level than "wind range" - so for example if you are a fairly advanced rider, you can start using this wing at 15 knots, from 20-35 knots is probably the best overall range. Best type of use is in the waves, although for lighter or advanced riders also a great option for flat water, some of our lighter riders using these for racing too. For me at 76kg's, I liked the 750 from about 20knots upwards, but of course I have access to all other sizes too, so using a 900 in 10-20knots is just a bit more comfortable, at least in smaller waves.