Make no mistake, the Sigma is a big lens (82mm filter diameter) , but so far it seems very well made with solid manual focus characteristics. it is roughly the size of the 5DS body and maybe heavier. No it doesn't cover a very broad focal length range (I wish it were a bit wider - like 20 or 21mm but that likely would have made it even larger and heavier) but that may be one of the reasons it optically performs so well, especially for a zoom.
I expected to lose some resolution once I got past f/8 but even so at f/11 it holds up well. I chose f/11 for the depth of field so I wouldn't have to focus stack. I'll be looking for chromatic aberrations i the forth coming days.
