I dont want to start an arguement but saying that a volt watch can pick up problems a load tester cant is flat out wrong.

A Hanger 9 tester like http://www.troybuiltmodels.com/Voltagetester.htm the one there can test up to 2amp load. A volt watch simply cant do that. Its one thing to move the sticks around on the ground with only surface load... but doing it in the air is different, there is now a load on that surface making the servo work harder.