How to choose your windfoil ?
Sail with or without cambers
Cambers provide power and stability in the high rpm range. However, this also means heavier sails. The higher weight means that you need more wind and speed before taking off with a foil.
A sail without cambers will be much lighter and more flexible. It offers more dynamism to take off and fly easily. On the other hand, it will deliver less apparent wind in the low rpm range, which will make it less fast in this area.
For high speeds, a sail without cambers will have to be quite stiff with a taut leech to be effective.
With or without cambers, the choice will in any case be towards a slender sail rather than a compact one. Indeed, a large and flexible head could create movement which would be reflected in instability on the foil (pendulum effect).