I'll probably get grilled for this, like with my "400 foot woodie?" topic, but I don't think there is a limit, except what people are willing to board. To that I would even say people will board almost anything! The GP will assume, "if they can open it to us, the GP, it must be safe for us, the GP!"
G forces can be controled by adjusting the angle of decent and probably other factors. In my mind, the only problem that would be difficult to overcome might be wind speed; or should I say, bug speed!
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ATTENTION!!...This is the Alter Ego of Goliath Rocks; If he said something stupid, we're sorry, it's the "G"s talking...