whwiden's post is likely the only one with merit here... You seriously need to study Thom Hogan's review
http://www.dslrbodies.com/lenses/nikon-lens-reviews/nikkor-zoom-lens-reviews/nikon-70-300mm-f45-56-af-p.htmlhave both the DX and FX versions...
Picked up a "white box" DX version for $210 (new) via walmart... It works great!
Purchased the FX variant from B&H (it was defective and I had to return it) B&H said no problem and sent me a good copy.
My thoughts after using both? the DX version offers the best value by far... and is only a tad less in optical performance...
The down side is you must upgrade your D7100; D7200's firmware to use this DX variant... It does NOT work on the D7000 (what was Nikon thinking?) Also the DX version does NOT come with the appropriate HB-77 hood which I had to purchase separately for $25.95 from B&H... outrageous... btw, you simply can't use this DX optic in sunlight without the HB-77.
The FX version has a slightly better build quality (but certainly not a lens I would use on a commercial assignment).
The FX version is optically very good between 135mm through 200mm (which is where you would likely be using it)
Outside those limits it is only marginally acceptable... period! At 300mm acuity loss is certainly unacceptable for commercial work and it vignettes terribly...
What's to love about both lenses? light weight, Focus speed, silent AF, and absolutely amazing VR... likely one of the best Nikon has produced
For the price point... both represent excellent value... but again, they are a hobbyist tool (not weather sealed) and rather fragile.
For shooting commercially look to the 80-400mm (new version, the older version is a dog). You will not regret this choice...
https://www.bhphotovideo.com/c/product/936121-REG/nikon_80_400mm_f_4_5_5_6g_ed_vr.htmlThis optic is widely used by commercial outdoor sports photographers...
Below please find an example of the DX version... not bad for $210... at least in my humble estimation...
Hope this helps or is at least food for thought...
I wish you well on your journey augieg27