I am looking to pick up a used DJI Phantom 2 Quadcopter With a Zenmuse Gimbal for a GoPro4.  How hard is it to pull the GoPro4 from the gimbal? I like the idea of being able to use the GoPro4 when I am not using the drone.  
Thanks,

Easy, peasy...

Two screws to remove the Camera securing bracket.  Some versions of the gimbal have a USB connector that plug into the side of the camera rather than using the connector slot in the back of the camera.