I use 2 Saitek throttle quadrants, 1 prop-RPM lever, 4 throttle levers, and 1 lever for all carb-heaters. For the reverse-handle I've set up the "buttons" in the reverse-zone of the TQ. So I can pull back the trottle levers to idle, move one of the levers into the reverse-zone of the TQ to trigger the reverse-handle, and then add reverse-power by moving the throttles forward. To return to normal prop-pitch, same procedure again. Works like a charm!
Never tried by using Buttons only or by pulling the levers with the mouse.