The 650 with NEX and 3 axis gimbal with 15" props and 530kv motors was too under-torqued. Resulting in a crash. It can barely fly with 14" SF props but she has to work really hard to keep it in the air with barely enough lift to move around with. Biggest problem= not enough motor/prop.
I added the Tarot 16mm Clamp Motor Mounts, stretching the frame from 650 to 750 which will give me more room for bigger props and more powerful motors. [URL="http://www.tarot-rc.com/index.php?main_page=product_info&products_id=1049"]
As of Feb 3, 2014:
Here's my build in final tweak phases. It began as a DJI Phantom & has morphed into a far superior Aerial Cinema platform. Flight time is about 5-6 minutes with 2x 4s 5000mahs batteries. Approximate AUW 3780g
Here's a list of the original components from the Phantom: $689 at time of purchase