I use this setup for landing, almost all the time and it really helps to settle the plane into a great glide slope. At faster speed it causes it to gain altitude, but once out of the box, who cares.

I have used these to get a plane to "stall" for a spin. It creates a slower, nose high attitude, so the nose will "fall" to score better. When I was using this, my plane wouldn't "break" so would zero the spin. It does make going through the sequence interesting if you forget to turn off the switch though.

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