I would say that for the moment nothing can come close to a hacked GH2 on Z15g gimbal. In the range up to 4000€ camera.
You can fly 5D but there is no steady gimbal like Zenmuse on the market yet for that camera size. And you still need post stabilization and then you loose some image quality. And If you compare the size of a copter which you need for 5D or GH2 and some flight times, there is a big difference
If you would like to fly with DOF you need a good auto focus.(or another big heli with remote follow focus)
So here GH2 can win again.