I bought this lens used from a friend of a friend over the Internet. It looked a bit beaten up when I finally got it and I had a moment of panic. However, I put it on my camera and soon found that it performed flawlessly. Given the external condition, the fact that it still works perfectly is probably a good testament to its durability.
The colors and sharpness are so much better than any other lens that I have owned that I find myself using it when I really should be using a wider or longer lens.
Yes, it's heavy and if I have two cameras going at once I have to be careful not to crack it against anything when it's hanging over my shoulder. But that is a minor price to pay for having a lens that produces such high quality photographs.
I highly recommend this lens. If you are buying one used, be sure that you get the version described at the beginning of this topic. There are several different versions of the 80 - 200mm including an older push-pull version. Make sure it says "AF-S" and "silent wave motor" on the nameplate. There are some unscrupulous sellers out there and the other versions are not as good as this one.