The Tamron is an f/2.8, so your camera will be more accurate with AF, but it's a BIG lens with allot of glass. The AF speed isn't horrible, but it's not exactly a marathon runner on the S2/D100/D70's cam900 AF system.
I've seen a few of these at weddings and used as portrait lenses which is where they fit best IMO. They were being used on D1x's which would make the AF speed less of an issue having a faster AF system in-body.
The lens is very sharp. The samples on Pbase I posted are at f/9 or f/11 - I'm too lazy to check the EXIF - and were done in JPG Fine. I considered the lens before I got my Nikkor 28-70 AFS. I would say that the Tamron is a nice substitute for the pro Nikkor and is half the cost. It's not built like the Nikkor, nor as optically strong wide open, but it's a steal for the price and f-stop.
It's a heavy polycarbonite body with a big lens hood and did I mention that it was BIG!?
Filter Size 82mm
Maximum Diameter 3.4"
Weight 1.93 lb
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