Finished Guinea Pig but I added more candy bombing space per my kids request so the -500 series. I added 5 inches of cabin to allow a little more cargo capacity for other experiments. I also rigged the door to open and close and will add that to the pictures later. No gear saves weight and I belly land everything on crappy grass. My son sacrifice two Lego dudes to fly. Maiden flight is coming!! Soon as I get a day with no rain or little wind.