The first time I used this lens, I was a bit dissapointed. I could find the sharpness like my 35 1.4L. The reason was that my art had e terrible backfocus of +18 on my 5D MK3's. After Sigma calibrated my lens, I had a nother lens!
Sharpness after calibration Bokeh Color Fast AF
Nice build but scratches quick | Sigma hasn't the quality control as Canon No service for professionals like CPS from Canon