One odd thing about the 200-400 VR lens that Thom Hogan noticed after shooting it for well over a full year (more like almost 2 years) was that it was VERY sharp at closer ranges, such as 80 meters and inside that distance. I cannot do justice to his review of the 200-400 here, but one of his analogies was like, "With the 400/2.8 you can see the bear's fur as bear FUR, even at 100 meters distant, and can clearly discern individual hairs, but with the 200-400, that is not the case." He pointed out that at "normal" and "close" distances, the 200-400 was impeccably sharp, and the images looked fantastic, but that as a long-range telephoto, the lens is a notch below the prime Nikkors. Again, look at the Sigma prime's MTF charts and pay close attention to the frequency....do not compare MTF 20 versus 30
Ahhh. I see how this could cause a misconception, but both the Nikon and Sigma MTF charts measure accutance at 10l/mm, and resolution at 30l/mm....the Nikkor is *significantly* better...sure, you can goose the sharpening in post...and bring the Sigma up to an un-sharpened Nikkor image...yet still, the Nikkor offers what I would call substantially better image quality. Look again...I think you ought to read the Hogan review of the 200-400 VR and re-evaluate the "ever,never" aspect
Will do. Thanks for posting it! :thumbsup:...IMHO, the 200-400 was designed as an arena/field sports lens, NOT a wildlife lens

; it's gained a lot of popularity for endzone-stationed photographers covering American football and major league soccer under professional-level arena lighting.
Nikkor 200-400mm f/4G Lens Review by Thom Hogan
What do you want the lens for?
Idealistically, I'd like it to be primarily a wildlife lens. But, that being said, I am kind of counting on it being able to cover any sports games (outdoors, daytime mostly) I may want to shoot. How important is focusing speed and focusing SURENESS???
Obviously they're both crucially important. But I'd say focusing sureness is more important for me. I rarely miss a shot with my 80-200/2.8 and D300s due to tracking issues. If the focus speed matches that, which, any lens with a AF-S/HSM should, or even surpass, then I will be happy. Focusing speed, and sureness, reliability, dependability of focus, in both ONE-shot and tracking...that's where the Nikon and Canon 300/2.8's really shine...I don't want to knock Sigma unfairly, but every review I have read indicated they are " a notch below " the big-maker 300/2.8's
Fair enough.. The new Sigma 120-300 I have not heard much about except from M.R. at TLL, and he praised its optics. A good example in focusing would be say,the Nikkor 300/4 AF-S versus the 300/2.8 AF-S Mark II: I own both lenses. The f/4 model will occasionally FAIL to focus on track and field uniforms that are bland, or in poor light, using center-point AF; the 300 AF-S II model is world's better.
Good to know, as I will probably be picking up a 300/4 AF-S to hold me over before getting one of these bad boys. That's kind of one of the things you need to hear from an actual user who's going to use the lens for a purpose similar to yours...the way I see it, for news/sports/event coverage, the ZOOM capability is a big plus. Advantage Sigma. For use with a converter, the advantage is probably going to be with the VERY-newest Nikon aspherical converters, paired with the "newest" Nikon VR-II model primes and zooms
This is simply not an option. 
. For pure focusing speed, accuracy, and reliability, over say a three-hour football game, my bet is that the best-focusing lens would be with the 300/2.8 Nikkor over any zoom or any Sigma.
One thing is for sure: used lenses in this class cost a lot less than new, and the Hong Kong price of $2,400 or so...hmmm..what does Tri-State sell the 120-300 for? They are a good gray market retailer.
They have the non-OS version listed at $2,999, and the OS version at $3,199. Same as everyplace else.