Would you sell a Sigma 70-200HSM to get a Nikkor 80-200 AFS? I've had two Sigmas and two Nikkors (w/ and w/o tripod collars) and there was not enough of a difference in image quality to rate one over the other optically. I have not shot the AFS lens...anyone shot both? I'm in search of hands-on experience here. I'd prefer to avoid hearsay (what's been read or heard). I would rather not give up the wide 10mm unless the 80-200AFS is that good. Thanks all.