I am just getting more, and more confused about the controller. After I received a defective unit the first time, and it fell out of the sky on first flight. They sent me a complete replacement. But I used to have the GL300C controller, and the replacement remote prints: GL300B. What is the difference between C and B? I am quite confused. Thanks. The difference is probably not big, and doesn't change anything, but I am just curious. Anyone knows?