This lens is good as Nikon 70-200

Perfect

Sharp and Fast

High sharpness at low price. The same type of non-third party lenses (official brands) costs twice more, but the results are very, very similar... Recommended 100%!

My second favorite lens for concert photography. I use the Sigma Art 50-100 mm lens 1.8 for very dark close venues and this lens works great if I am not able to get so close to the stage. With f2.8 it does well in the dark, changing light environment. Quick and sharp focus

Great lens. Not as fast as Nikon's but the price compensates for that.

Sigma's New APO 70-200mm F2.8 EX DG OS HSM is the second generation of this large aperture telephoto zoom lens now incorporating Sigma's Optical Stablization function, OS, our own anti-shake system which makes viewing a stabilized image in the viewfinder possible for Sony and Pentax users if chosen.

I debated for a while on whether to wait until I could afford the Nikon version or going ahead and getting the Sigma. I have a trip coming up to Alaska so decided to go ahead and give the Sigma a try. I have only had it for a short while but so far I am very pleased with the results from this lens.

The Sigma 70-200mm f/2.8 DG OS HSM Sports lens is bigger and heavier than all of its main rivals, but we can forgive that because of the compelling mix of fantastic sharpness and image quality, great build quality, and outstanding feature set and performance.