I have a mint condition 24-105 that looks brand new still. It will come in the original box with the lens hood, caps, manual, warranty card and leather bag, and will even have the original styrofoam molds in the box and the plastic bags.
The optics are perfectly clear, not a spec of dust in them anywhere. UU date code (UU0807) The lens has done me very well and I'll definitely miss the nice long range as well as its astoundingly good image stabilizer. There is not a smudge or scratch anywhere on the lens body.