Not an answer to your question, but I have the Schmidt Son 28, which is great. Have thousands of miles on it, mostly with the power running and it works great. Pretty low drag while running, but the hub is a bit heavy. If I were getting a new one, I would get the Son 20 which is a bit lighter, but has enough power to run a LED light. See Peter Whites website for more info on generators and lights. He built my wheel and I have been happy with the job he did. He is a bit of a curmudgeon though.