As was said above, you're going to get a lot of different answer. I of course range check a new plane, or when I've done any work on one. Then I will check them every other trip to the field. Range checks should be done with the engine running, both idle and full speed. Yes, you need to secure the plane before range checking it with the engine running. I use a piece of rope and a tent stake, or you can get a buddy to hold the plane while you do your range check.

Ken