RE: Lanier Ripper, didn't like the first day of spring.
I set up my engines so the carb can be completely closed from the throttle lever. It's amazing how much dirt you can keep out of the engine by pulling back the throttle before impact. A spring loaded switch is a good idea for a quick throttle kill, but if the throttle opens back up before impact, it wouldn't be as good.
With the MAS props, I usually set the prop to be horizontal when the engine dies, but sometimes I don't bother. If you land smootly enough with the engine dead, the prop will frequently just move out of the way and not break. I've even landed engine-on with out breaking the prop, and that was with planes that don't have a skid, so the engine is much closer to the ground. It can be done, you just have to bring it in real smooth.