you have the AF-D 300mm f4 (500ish used) or the AF-S 300mm f4 ($1000ish used), both are great lenses, you won't find anyone here who doesn't think they perform admirably for the price. but since the 2000 release of the AF-S 300/4, people have been wanting an updated version with VR- the problem being the 300 2.8's that have been updated since then with VR, are much pricer. nikon has yet to see a need to close the price gap in bettween the $1500 F4 and the $5000-6000 VRII 2.8. perhaps the nikon 300/4 doesn't sell well enough to justify making it a $2300 G VRII N lens. your other options around $2000 are the AF-I 300mm 2.8 (1600-2400) or the AF-S I 300mm 2.8 (2500-2800). both great lenses- many like to shy away from the AF-I lenses in fear of not finding repairable parts for the focus motors, from what i've heard that isn't a huge issue. (old school 1986 AF ED 300 2.8 is also an option- got one for $1300 off ebay a few years back).
I wouldn't worry about the D800 "outresolving" the 300/4 AF-S. Does it outresolve the D7000? Nope, and that's a comparable pixel pitch to the D800. It's a great lens -- the best 300mm Nikkor, short of the f/2.8 versions.
What it will do is reveal every blemish in your technique -- it's a lens/camera combo that will shine brightest when properly supported.
I am using the 300/4 AF-S on a D5100 until my D800E arrives. Does great on the D5100, same sensor as the D7000, close to the same resolution as the D800 in DX mode.
Don't forget the older still 300/2.8 AI and AI-S lenses. Very sturdy build and can be had for as little as $700 from KEH in BGN condition. Around $1000 gets you better condition or more accessories. Focusing these will take some practice though...
Depending on your output requirements, the 300mm shot wide open might not accomodate your quality requirements. If you have decent output sizes, thing are fine. The closer you get towards 100% in images shot at f4, the more you see limitations of the lens (at high level)
The 300 f4, I think its plenty sharp. Below is a 1.2X 24MP pic from D800 (out of camera JPG with sharpening set to 5) and a 100% crop. Did not have LR or PS (now) to process it so this is a straight out of camera resized/cropped in paint to 1200x800. You can definitely do a lot better with LR or PS. This should give you an idea of the lens capabilities on D800.
I am actually suprised how well some of my cheaper lenses work with this megapixel monster
Mostly I was worried about my 70-300 VR. When I tested it, it was performing really well. On my sample there was in the right side of the image something like 200px wide part which was clearly softer than rest of the image. I can post some examples later when I get to my computer.
On the other hand. I tested 24-120/4 with this D800 in a store and 85mm-120mm end looked terrible. Have to think again before bying that.
I would also regommend 300/4 AF-S if you need the speed. It's much better than my 70-300VR and I just sold mine, because I needed the stabilizer.
