RE: your harshest GST runs and the limits...
I live in a skatepark and I beat the crap out of mine. The only thing I broke was a upper arm,plastic shock body,and smashed cooling head. I do some hard hits . Hopfully I get a video for you.{EDIT}For the water and mud question I just drove tru about 5 or 6 inches of water no problem on the edge of a pond.