400 lbs is WAY more than we deal with in RC. YOu're into Ulltralight territory witth that one. Full sized "rules" willl definetly apply. If it's getting kicked around then it's due to the design choices made by the design team and not related to it's size. But there's no doubt that the key element, the reynolds number operating range, is going to be similar to experimental homebuilts and ultralight aircraft and likely an order of magnitude over what us RC guys deal with.