Update 8/27/10 It looks like I may have a defective unit. The manufacture has offered to take it back and replace it so that is very nice of them. Once I get the new one or get more feedback I will post it here.

UPDATE- As of now 8/26/2010 I'm quite sure the FY21AP is not an inexpensive but full fledged IMU. It's a stabilizer that will help steady the plane but you still have to fly the plane. It won't keep the plane straight with sticks centered. At least not in my experience. If you don't use gyros to steady your plane then this unit might be worth it to you. If you do then perhaps not so much. :-)

If you look at the downlink video closely you will see that the wings of the Artificial Horizon in the center stay with the plane instead of tracking the horizon. I believe this is why it didn't work very well today. Perhaps I need better tuning but I was disappointed.