The problems should not be the aperture and the mechanical focussing but those elements that need (micro)drives in the lens itself like AF-S, HSM andimage stab.
After I've heard some stories about the longevity of the AF-drives in lenses I wonder whether it was a good idea to put such a sensitive elementin a lens instead of using the drive of the cam-body - as we all believe(d) that lenses should last much longer than bodies
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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