I have the original DJI Phantom 1 and want to put in the biggest sized battery for max flying time. I don't mind cutting out the door frame a bit to allow a battery the extra size. The question is what is the maximum battery I can use. I looked at the 5000 mah batteries but I think the 43 mm is to tall a dimension on the zippy. Any suggestions as to what I can use? I don't want to use the double batteries on each side. My friend tried that setup and the straight down descent was a disaster. I hear there is a rocking problem, which i saw. So I want to use just one large battery. Any successful people out there?