As promised, I will now add my personal review regarding the AF-S 300mmF2.8
This lens is a true work horse. It's also as big as a horse and isn't a practical lens for everyone. I will compare it to the 70-300, 70-200 and the AF-D 300mmF4, all of which I also own and have used extensively.
Size and features:
There's no getting around it, this lens is big! I had to buy a new backpack just to be able to carry it. The lens hood looks as if it were made by cutting off some large cylinder or pipe. It's plastic and has a screw to lock it to the end of the lens itself. The lens cap is leather complete with draw strings and Velcro fasteners. Unlike the newer versions of this lens, it has only two switches; the AF M-M/A switch and a focus limit switch. It's non VR so there's no switch for that of course. Filters are the drop in type which go in a holster near the lens base. It takes 52mm filters there. Like the 70-200, there are several AF buttons near the end of the lens surrounding the barrel. Like many AF lenses, the AF can be over-ridden by simply grabbing the fat manual focus ring. The action of this ring is a bit stiff but still works fine. I don't know if this is a characteristic of this model or just the copy I have. This ring is also a royal pain in the ass, I'll explain why later. The tripod color is typical for a lens of this type and time period. The tripod foot seems a bit flimsy. I've not yet mounted this lens on my tripod to test this out.
A lens like this requires different handling techniques than what we might be used to. With my 70-300, 70-200 and 300F4, I simply either had them attached to the camera already or I just picked them up and mounted them on the camera. Yeah...not gonna happen with this lens. First, I got the Lowepro pack that wasn't large enough to have the lens mounted to the camera. I still needed to be able to carry on a plane and at least with Southwest Airlines, this is entirely possible.
So what I do is take the lens out with the cap and hood over the end of it. I stand it face down. Then remove the rear lens cap. The camera is then mounted to the lens in this position and the camera is twisted into the locking position. I've only used it so far on the D300. I'll test it on the D90 at some point later perhaps. Now the comparisons; The little 70-300 can just be mounted and warm around the neck of most people. Typical consumer grade lens. The 70-200, if the tripod foot is attached should balance pretty well on a D300 and normally my 300mmF4 does as well. The 70-200 for example will stand on the tripod foot with neither the camera nor the lens touching the service. Not the case with the 300mm2.8. Because it is front heavy, it tips forward. This creates another problem; because the front is so large, it rolls...a lot! If you get this lens and set it down, even when mounted to a camera, be careful, it could very well roll off of a table! It rolls in wide circles but could still crash. I was lucky enough to watch this when I got and thus far have managed to avoid any accidents.
Once you pick it up, the girth will be noticeable right away. This is the largest lens that I think I can hand hold. Not so much for the weight although it is heavy. I hand held this lens for hours on end. It's balancing that's a huge challenge. Remember when I said that AF ring was a pain? Well the area where you would cradle the lens just happens to be where the AF ring is. Frequently, I found myself screwing up shots at the last moment as my hand would move the AF ring right before I fired. For this reason, if you hand hold this lens, you have to hold it further out toward the end. This requires more balancing which in turn requires strength in the left arm. I'm a weirdo, I am strong and I have large hands with long fingers and can adapt my grip readily to most things. For normal people, this lens is likely not hand-holdable. This is perhaps why the newer versions are not as fat and have their features placed differently making hand-holding more possible especially with the VR versions. As with all large lenses, I suggest a carrying technique that has you tucking the lens underneath one of your arms near the armpit pointing behind you. Then letting the lens itself rest on your fore-arm rather than trying to bare all of the weight yourself.
Now to talk about why anyone would get this lens. My first telephoto was the 55-200. I used that lens on a D40. For normal people, this is a good combination. My type of photography is far more demanding however. With that combination, I would fire off 5 to 10 shots. I might get 1 to 3 that were usable. Very occasionally I would get one really good one like this http://www.pbase.com/shonn/image/94772298. That was very much the exception to the rule. Later, I got the 70-300. This lens was a better performer overall and I have more keepers in general: http://www.pbase.com/shonn/image/103272348. These two lenses required a lot more post processing to get things just as I wanted them. The problem is that they become soft and touchy when pushed to their extremes. Problem is, wildlife photography, especially birds are done at the extremes. Sharpest results with them were achieved when stopping down to 7.1 or F.8. Too dark and AF often too slow for any real work.
Next came the 300mmF4. and the 70-200VR. These two lenses are very similar in what they can produce with the 300mm perhaps a step better, not just because of the FL but IQ is perhaps a bit better as well. These two lenses are fast enough to catch birds in flight, much more so than the two consumer lenses. Also, the focus with these two lenses is much more accurate. Less time is spent in PP although colors can sometimes be a bit flat for my taste. Both are much sharper than the 55-200 and somewhat sharper than the 70-300 below 200mm and noticeably sharper above 200mm.
Now how does this 300mm2.8 compare to those two great lenses in the performance area? I won't even mention to consumer lenses anymore. Sharpness: It is sharper than either of the two lenses mention before and those are already sharp lenses! Less sharpening is needed when post processing and sometimes you can get away with none at all. Saturation: Oh this lens saturates colors exactly how it should. For the first time, I do not need to touch my colors when post processing. However you have your camera set, it will show the colors accurately for that mode. The colors are neither too flat nor do they bleed into other areas. So this meas that contrast is also very nice. AF: It's an AFS lens so it is reasonably fast. I say reasonable because this is a big lens. Therefore, it's AF is slightly faster than the 300mmF4 in most situations. Lightening fast in good light. Slower in poor light but it hunts less. While AF-S is known for being silent, with optics this size this isn't always the case. When the lens has to go from one extreme to the other when focusing, you will hear a soft rolling sound. However this is still much quieter than the electric toy sound made by the 300mm AF-D lens. Otherwise it truly is virtually silent most of the time. When it does hunt, you may hear this rolling sound along with muffled but noticeable clicks as it tries to lock in. Another thing I've noticed is when shooting at high ISO's, for whatever reason, the noise seems less noticeable than before on my other lenses. Perhaps Alpha can address this as he seems to know about these things? Also, that Fo-Zoom thing mentioned seem to be a part of this lens. While also a 300mm, it seems to have more reach or at least magnify and image more than the 300mmF4.
So what's my conclusion? Overall I feel this is what I've been looking for in a lens for a long time. While the 200-400 was my original dream lens, I have adamz to thank for making me aware of this class of 30mm primes.
Hope you all found this informative. Keep an eye on the PAD threads for sample from this lens.