When spending $1000 on a lens, people expect perfection. As Roger Cicala of LensRentals.com explains in a very thorough post on dpreview however, perfection is an impossible task and hunting for the perfect example of a lens is futile.
I see this as good news. I have never been a ‘lens hunter’ myself, and in that regards, it affirms my choice that it simple isn’t worth the effort. I’m interested though, do you adjust the fine focus of your lens (usually available as a menu setting), or do you buy and sell lenses looking for the sharpest copy?
If you want to touch-up your focus, BHphoto has a nice video tutorial