Summary: lens is sharp has a sturdy weight to it easy to use. Barrel twist is easy. The color is a bit dust looking and when I turn off the camera I hear a slight click or thud as is the lens shuts down. It doesn't seem to have an effect on operation. But it just not normal. I would recommend this lens.
Summary: I shoot it a lot and its got great contrast and sharpness. If your leaning out of a helicopter you have to be wary of the 'zoom creep' (shots made on sharp incline or decline) and just 'touch' the zoom when its where you want it.
Summary: its ok I sold me 28-70 nikon and like a fool thought i could get buy with this till i got my 24-70 f2.8 NO!!!! dont get me wrong sigma makes very good pro glass idk what anyone says .. but if you want best 3rd party glass and i can create an arguement that it's not 3rd party go with tamron!!!!!