Lol, yeah I did. And I actually tried a bit today myself. Got out my sons RC car and drove with my toe and shot off with Case 2 and 4 point, and it nailed 9 out of 10 shots, even though it was close and goes pretty fast. It's looking up..
No offense, Viggo, but this is starting to sound like lens witchcraft: the Sigma 50mm works right if there is a full moon, you balance on your left leg, and say "boogum" before you turn the camera on. I probably wouldn't tolerate a lens with these autofocus issues--I'd send it back for an exchange or refund. Sigma should offer to "make it right" on every one of these lenses which doesn't perform. Perhaps they'll get the message when they start choking on the returns.
The purchase exception, from my perspective, would be for folks who are willing to accept a manual focus lens but can't afford the Otus 55mm or TS-E 45mm II, or can't wait for the likely fall/winter release of the latter.
I'm happy for folks here who own one that they are finding ways of making the Sigma work for them, and kudos to Viggo and others who are sharing their secrets of getting some autofocus performance. But I'm quite saddened to hear it is such a flaky product out of the box. Very disappointing design and quality control, especially for a leading product that is more than double the cost of the comparable Canon. My recommendation to others will be to wait through 2015 for a possible Canon upgrade if they really want an f/1.4 with autofocus. This result puts a pall over the entire revised Sigma lineup for me.
But I respectfully disagree with you, but I felt the same way you do about the 35 Art. But the 50 is an epic lens, it really is. Canon almost have no lens comparable, and no where near the IQ at 1.4. It's close to my 200 f2 in all aspects, distortion, CA control, sharpness etc. I'm not saying it's 100% equal, but it's very close, and that is pretty crazy. It makes me very annoyed with the 85 L and it's ca issues now, again, crazy.
The AF is much better than 35 Art I had and it's veryvery stable, when the contrast is there.
And as for calibration I applaud Sigma for providing the docking, their hands are tied when it comes to AF patents that Canon and Nikon have. And that the provide a solution to overcome that and really have a tool to make it hit perfect is awesome, and it's not very expensive either, even if you have only one Sigma.
Here's a shot at 1.4 in indoor daylight. I can live with annoying AF misses for IQ like this and the good AF performance you get.