Excerpt: I am mainly a prime shooter but got this lens because a fast zoom can be useful in situations where you cannot switch lenses. Prior to buying this I rented both a Tamron 24-70 and Tamron 28-75. My plan was to buy the 24-70 but as the 28-75 was a cheap rental I decided to try it too.
Excerpt: Not bad, not amazing. Don't expect that just because it's a 2.8 lens, it's going to be amazing. Image quality on par with kit lens with advantage of low f stop. Zoom is kind of stiff, not smooth.
Excerpt: I found this used in a local photog shop in Bismarck at half new. I was lured by the 2.8 across all focal lengths. I am very pleased with this lens in the test shots I've taken so far. The autofocus is a little noisy and sounds kind of weird, but hey, it works fine.
Sharp, contrasty, medium-speed AF. Overall, great for the price
1 March 2015
Summary: I used this lens on a D40, D90 and D4. Nice and sharp after f/4, nice contrast and colors. Colors are more on the warm end-- takes really nice looking photos of metallic and "natural" colors like brown, green, etc. It isn't marketed as a fast/sports focusing lens, and..it isn't.