its hard to get the gyro to lock in, i had to peel off sticker off of front of gyro there is a trim pot screw right next to gain, i turned it bout 1/16 or a little more but gyro then would hold in hh mode and arm stop moving when switching to rate mode, in hh mode gain at 56% and in rate mode 23% but still acts up some times its not worth crashing over a chep gyro, guess a 401 is best for the money,and can depend on it. think helimax would had done little more home work on the hm4000, the set up is nice and easy to work on