This controller is absolutely terrible, and they know it! If you would like to see what a persistent problem this is go here:

http://www.knifeedge.com/forums/show...8415#post68415

and here:

http://www.knifeedge.com/forums/show...t=15951&page=1

My controller spring failed after less than a month of use. Product support said this is a KNOWN problem, and send the controller back. I spent $11 sending the controller back. They had it for a week, then sent it back (the slowest way possible). I expect to maybe get another month of flying before the controller breaks again. This is after spending $200 for an RC sim. Ironically I went to the local hobby shop today, and saw that they are now selling the Realflight 3.5 sim. They had a display set up, and I went to fly it. Guess what? The controller on the display had broken springs and wouldn't center. If I knew then what I know now, I never would have bought this sim, but of course I have too much invested.