I was disappointed with mine through Adorama even though it was supposed to have been pre-tested. Sent it to Sigma and got it back Friday. They claim they updated the AF software. Did some sample shots inside on Saturday and then from my Balcony Sunday. In most every case, the lens focused much, much better than it did before and there was very little difference between indoors and out, and distances were far better handled. A license plate on a car 30' away was just as sharp as the logo on a bag of top soil 5' from me. (I used the dot tune method of setting my MA, which is at -12 right now)
Going to be snapping more pics at lunch. I currently also have a 35mm loaner through CPS, so I am comparing both lenses side by side. The Canon also needed MA on my camera of -9 using the Dot Tune method. It seems as though the Sigma actually hits focus a bit more often than the Canon does, and when they both hit, the Sigma does actually look slightly sharper when magnified to 100% and beyond.
There are still enough missed focuses to make me wonder, but hopefully with some more testing and practice with the lenses this week, those numbers will come down.