I got my own copy of the 300/4E PF yesterday and took it for a spin at an outdoor concert. Compared to D version, I find the following advantages
+ gives quite good image with TC-14E III at f/5.6 (I always felt the D version with the TC-14E II was a bit fuzzy and required stopping down to f/8 which made hand-holding difficult in part due to the absence of VR). My 300 PF+TC-14E III is better at 420mm, f/5.6 than my 80-400 was at 400mm f/5.6 but at f/8 the zoom was very good.
+ autofocusing (with D810) is less jittery than with D version, less variation in focus from shot to shot, though with the TC mounted the focusing started to be more variable; probably my hand-holding contributed to it, but it seemed that there was a definite loss in AF performance with the TC-14E III. I quickly tried TC-20E III as well, focusing was very slow. Maybe better in brighter light but it just didn't seem like a friendly match.
+ superb handling, it almost feels like the lens floats in mid air it is so light
+ I tested the VR of my copy (208xxx serial) and it worked very well at 1/50s, 1/100s, 1/200s and 1/400s in Normal mode, with the 1/400s being sharpest but all were quite sharp. VR in Sports mode seems to tolerate turning the direction of the camera with faster response in the viewfinder while the Normal mode fights changes in direction of turning a bit, so if following a moving subject that changes direction, sports mode is probably the appropriate choice. I think VR performance is perfectly fine on my copy and it will serve the function that I need for it. However, when photographing living subjects it is still the case that I could observe slightly improved sharpness when going from 1/500s to 1/1000s, this I find to be typical in using high resolution cameras. So: my thinking is that "acceptable" or "good" results can be obtained from slow to medium speeds but the very best results in terms of subject detail still come from high shutter speeds. I haven't used the 300 PF on a tripod yet. I have the RRS collar for the 70-200/4 which should fit on the 300 PF as well, but I think it's better to mount the camera on tripod with this size of lenses. Testing of 300mm PF tripod mounting from collar and without will happen soon. TC may change the balance and behaviour as may the use of a vertical grip.
+ I shot in a bit of rain, front element nevertheless appears pristine so fluorine coating appears to work so far as advertised. Good sized hood also does its job in reducing spray. I think this is a good lens to use for sailing pics (boat-to-boat) since there can be salt water spray, rain, wind, and quick movements required to stay safe so a compact lens is easier to work with. I don't think I could be sure to make a 300/2.8 survive without bumps in sailing action in wind and adverse weather...
+ High contrast fine detail such as hair displayed very sharply with the lens at f/4.
+/- Out of focus rendering is generally nice but not as consistently beautiful as with some other telephoto Nikkors
+/- Colour rendering close to that of other modern nano coated Nikkors.
- low contrast subject matter in low contrast light appears a bit bland and hazy. S curve in post-processing may be needed to compensate in such situations.
I didn't have the kind of subject matter which would have made it possible to evaluate the corner performance (which in some tests was found inferior to that of D version). But overall I think it is the right lens for me to use for outdoor stage performer close-ups. It gives acceptable results wide open with and without TC-14E III, is easy to bring along where-ever I may go, can be hand-held indefinitely (as opposed to e.g. 200-400/4 which I can hand hold for maybe 30s
) and it gives sufficient range and detail for pretty much all my needs that are not covered by shorter lenses. The only glitches from my point of view are the AF performance with TCs which needs further evaluation in more favourable conditions (brighter light!), the slightly bland results in low contrast light, and bokeh which is sometimes excellent but sometimes I get result that looks a bit "odd" and requires some getting used to.
I think the colour contrast of the 200/2 II is better than that of the 300/4 PF, and this means the results in this kind of ominous dreary rainy day light look better and have more "pop" from the 200mm than the 300/4 PF. But then we're talking about a different product entirely. This makes me a little bit ambivalent about the 300/4 PF but I hope my mood improves when the sun starts to twinkle between the clouds and weather and light get better.
I've now used it for about six hours with about 900 shots. I give the lens top points for handling and features, including VR and AF performance, while optical quality has some slight minuses observed so far (maybe school grade 8 1/2 or 9- in my subjective scale), but may be a question of getting used to the rendering of the PF optics and finding its best use scenarios. As usual there is some learning curve to finding what a new lens is good for and where its weaknesses may lie. I think I am happier with the 300 PF than I was with the 80-400 and I think it will complement 70-200 type lenses well especially when carry-on space and weight are restricted, but if someone specifically needs 400mm and not 300mm, then I think the 80-400's focusing may be better able to deal with the requirements of focusing at 400mm (somehow autofocusing with TCs is an area which takes many lenses outside of their home turf). Although it seems that some consider the 300/4 PF a replacement for the 300/2.8 (I've noticed this in the wind) I do not find that at all to be the case, the bigger lens is more like a production to use but it produces images with "pop" due to contrast, colour, and in/out of focus effect that I don't seem to quite get with the PF. I also think the 300/2.8 autofocuses with the TC-20E III better that the PF with the same TC, which is not surprising considering the maximum aperture. I don't think the 300/4 PF is the way to get to 600mm, but it seemed to be a reasonable way to get a portable 420mm.
Sorry for the long post
