My old primary setup of Nikon AF-S80-400mm VR2 and D750 DSLR was used as a video cam and photography tool for my wildlife shoot (especially for wild otters).
Roy
However, after I saw a friend of mine who uses the Panasonic FZ2500 for his video shooting on wildlife, I began to get interested in this setup. The video quality is very good. The important thing is that the FZ2500 is a bridge camera that uses a respectable 1inch sensor. I cannot really tell the difference between the D750 and FZ2500 video quality. I settled with the older generation FZ1000 which has a zoom range of 25-400mm. It also has the 1inch sensor and capable to shoot 4K video. Handholding a DSLR and 80-400mm for videography needs some arm muscle as I need to view on the LCD of the DSLR. I need to stretch my arm forward during filming. It is more challenging to get stable filming and hard to view on the LCD when under the sun.On a bridge camera, I can view the scene thru the electronic viewfinder and locking my arms while doing the filming. It is much comfortable and the setup of the FZ1000 is so lightweight. I enjoysthe video filming process on the Fz1000 much more.
D750 w 200-500mm vs the much smaller FZ1000 Panasonic
The bridge camera FZ1000 Panasonic that uses a 1inch sensor. I used mainly for video filming.
Since then, the Nikon 80-400mm lens was seems to be a duplicate for video and will be used for mainly photography as a full frame DSLR photo quality is still much better than the 1 inch sensor on the bridge camera. This is especially true when used in low or bad lighting sitiuation. The full frame sensor can stretch more in terms of shadow and exposure corrections etc.
So it comes to a point that I saw the 80-400mm too expensive to hold on to. I sold this lens at SGD$1700 and bought a cheaper 200-500mmVR at $1200SGD. The review for this 200-500mm seems to be good and I decided to go ahead with the purchase. Noted that all my equipment is bought used.
The 200-500mm exceeded my expectations. It is sharp! I am impressed. I once thought that the AF-S 80-400mm with NANO coating,made-in-japan lens should a great buy compared to the cheaper 200-500mm made-in-china lens. I was wrong. It seems that Nikon has designed a value-for-money lens on the 200-500mm and didn’t compromised on the glass quality. The VR mode works well during handheld situation and I feel it works better than the AF-S-80-400mm. One key advantage on the 200-500mm over AF-s 80-400mm is that during video shooting the 80-400mm AF-motor will make noises during the focusing while the 200-500mm remained silent .The build quality of the 200-500mm is very similar to the much expensive 80-400mmVR2. The focusing is quick on the 200-500mm. However, the 200-500mm is also heavier than the 80-400mm. To improve the weight distribution while carrying the setup, I bought a extra Peak design plate to mount onto the lens tripod mount and attached the peak design slide strap onto it. It is comfortable as it distribute the weight evenly.
Here are some of the images from the 200-500mm on D750.
Roy 
