From Roger Cicala's post on the Sigma 24-105
I generally let you know what my expectations are before I start, to hopefully let you know where my personal opinion affects things. The fact that I’m just posting tests of the
Sigma 24-105mm f/4 DG OS HSM Art months after the lens was released tells you a lot. I’m not excited about testing 24-105mm lenses; it’s almost always ‘another one like the other ones.’
Don’t get me wrong; these are useful and popular zooms for a reason. I’ve owned several and used them a lot. The focal length makes them superb general purpose and walk-about lenses. But designing a zoom that goes from retrofocus to telephoto is a daunting task. My conclusion for almost every one of them has been “decent from 24mm to 70mm and usable past that if you need to.” I didn’t expect anything different from this lens, Art or not.