Well cost isn't too much of factor, I'll be building them myself. I would like to keep computer-control out of it as much as possible by using balanced for optimum performane stators. The theory of which relies on airfoil shape and pivot point I sappose. As for the fan, or turbine end that will likley be a one piece composite part (remember 10ft. dia.). Try to imagine a ducted fan on a stick catching wind to light an led bulb.