Sirrith wrote in post #15863899
Then why on earth did you buy the 5DIII and 50/1.2?
The 50L has focus issues of its own (focus shift), but at least its a consistent issue inherent in the design of the lens, and something that can be overcome with the right technique. (ie don't focus and recompose, which you typically don't want to do at a large aperture regardless of the lens anyway). With the 50L, I knew what to expect, and was OK with that.
Quality control issues are a whole different animal though. I had the Sigma 50 1.4 for a bit, and it was missing focus sporadically for no reason at all. Did not feel like playing the sigma lottery or going through the hassle of sending the lens back to Sigma if I discovered issues beyond the return period, so I returned it outright.
The sigma 35 is a cheaper alternative to Canon lenses, but its still a lot of money to be paying for something that may or may not work out of the box. Was really hoping that Sigma had worked out its AF issues this time around, but doesn't seem like that's the case. I'm really hoping that the USB dock is a true solution to the problem and will be keeping on eye on it though!
edit: My thoughts are that slowing the AF speed down via the USB dock may be the trick. i.e., the 85L's AF is slow as molasses, but dead accurate.