3Rotor wrote in post #16679659
Yes it can still be a good lens. If it's going to fail it's going to fail. You have to keep in mind that the majority of lenses that come up for sale are usually well cared for owned by hobbyists barely putting them through their paces.
This. I looked mine over quite carefully before buying; I had a choice between one with lots of little chips and worn spots on the finish (and some wear on the mount) and one which had clearly been babied. It came with a 6 month warranty from the store and has been trouble free through many hundreds of shots over the last year. It needed microadjustment but is very consistent. I wouldn't hesitate to buy a high end lens like this from a local dealer, even not knowing who had owned it before. In fact, a couple of pros advised me to specifically look for this model when the mark II came out, as they knew a lot of them would go up for sale lightly used.
I would go so far as to say that it's superior to my f/4 which I bought brand new.