I’m looking to add a couple of lenses to my arsenal. I currently have a D300, a D80 an 18-135 kit lens, a Nikon 16-85VR, Nikon 70-300VR, Tokina 12-24, Nikon 50mm 1.8 and a Nikon 85mm 1.8. I could really use some fast glass. I definitely will buy the Nikon 35mm. But I’m looking for advice on the Tamron 17-50 2.8, Tamron 28-75 2.8, Sigma 18-50 2.8, and the Tokina 16-50 2.8. The Nikon 17-55 is out of my price range but if it had VR I’d make would make the sacrifice. I like the Tamron 28-75 a lot because it will also work on a full frame DSLR. But I’d be lying if I said that new Tamron’s with the slow built-in AF motors didn’t worry me. My question is how do these lenses compare to each other and the Nikon in accurate AF performance. Lens will be used on a D300 as the D80 is getting ready to be sold with the kit lens. I’m talking about accurate AF performance in relation to AF issues such as back-focusing and front- focusing issues. I know there’s differences in IQ performance in the lenses and they’re also sample variations. But a lens that is on the soft side wide open can be sharpened up during the processing. I have already tried this with sample images taken from all these lenses wide open. Also I always sharpened my pictures during the processing specially if they’re shot with a lens wide open. But unfortunately there’s not a whole lot you can do to save out of focus shots. So am I likely to get more accurate AF performance from a Nikon 17-55 compared to these lenses??? And do any of these lenses work better compared to the other of the D300??? Thanks again.