This is quite an expensive lens, but results so far make me believe it is worth every penny. I am using it on a D300, which being a DX camera, means this is equivalent to a 120-600mm lens. The VR system is excellent; as you look through the viewfinder whilst holding the lens, it obviously waivers around a bit, but as soon as you slightly depress the shutter release, the image in the viewfinder is rock solid; its fantastic. I have achieved great results at 1/60th sec whilst handheld, which for me is very good going. The autofocus system is very quick; but I also find it very easy to use on manual focus. As you would expect with all the electronics and glass, its a fairly hefty weight, but not uncomfortably so. The lens comes with a good quality case, which is useful for me as it will not fit in my gadget bag.
This is the most expensive item of photographic equipment I've ever bought, but I am very happy with the results I'm getting, so I think its worth the money. Highly recommended.