I had a chance to finally try the Sigma out and it looked cool, it felt heavy and big for a 35 f1.4. Loved the focusing ring, very good color and contrast. I used LV to focus, since it wasn't afma'd, and I wouldn't trade my 35 L for it because of sharpness, others will. But all of that wasn't really important. I wanted to see if the AF is indeed "same as the 35 L" as I've seen claimed, I have always doubted that, because the 35 L is fantastic. And I was right, the AF of the Sigma feels like the 35 L in slow-motion.. VERY slow... I'm not sure if people who have tested the Sigma vs 35 L have used a 5d, and the 1d X spins the 35 L faster because of the higher battery voltage, but it's not even in the same leauge as the 35 L.
So I'll take my small light, VERY sharp, superfast AF 35 L a million times over.