I used single channel ops on my P-120. I used the GSU to determine what throttle setting gives me approx 55k rpm for cool down. (it turned out to be four clicks up from idle on my 10X). When I'm read to shut down, I just push the throttle up four clicks from idle and wait about five seconds, then shut down the engine.

I recently set up a 9C on a P-80 for a friend and we had to reverse the throttle channel in the radio so the pulse width would go down with low throttle. After that, the fail safe set up was virtually identical to the 10X.