I have Ground Station installed in my Phantom FC40. I also wide landing gear and carbon fiber twin external battery mounts with stock batteries. With the FC40 camera, my airborne weight is 1236grams. With the stock batteries, the UAV flew at best laboriously with a short flight time. But with higher output batteries (25C and above) the UAV flew better with a more predictable flight time. Any one else have heavy flight experience to share?