Which would be better for my C100: the Glidecam HD 2000 or Glidecam HD 4000? Would the 4000 be too heavy? I make documentaries and probably will be shooting only a few minutes at a time of stabilized shots, so probably won't get the vest and arm. The 2000 would be lighter and easier to hold, but maybe not heavy enough for C100? Anybody have any suggestions? Many thanks.