He seems to like it:

But one thing remains a constant with this lens. It delivers the goods each and every time I bring it out or use it. From deep rich color, to beautiful black and white to nice creamy bokeh (background blur) that will not give you a headache, this lens shows what the Sony A7 system is capable of. I have tried the Sigma Art lenses. I have shot with the Canon 35L on a 5DII, I have shot with the Nikon 35 1.4 on a D800 as well as the Zeiss ZF 35 1.4. I have owned and shot with the Leica 35 1.4 Summilux, all versions. It is safe to say that I have had great experience with all full frame 35 1.4 lenses.

This Sony is the best one I have ever used for my tastes as it does everything right. Period. The one that comes closest is the Zeiss 35 1.4 Zf, then the Sigma Art 35 1.4. Last place would be the Canon 35L as it is getting a but (sic) long in the tooth, even when used on a 5DII or III.

I have a small confession to make: lately I’ve been thinking about building a full-frame system, and I’ve been torn between the Canon 6D and the Sony A7II ever since the latter was released. With 35mm being my favorite focal length, this certainly doesn’t make things any easier for me — or my wallet.