AFMA is almost required for this lens. I tried 4 brand new copies from Crutchfield. All 4 copies have back focus issue. I ran all 4 copies through FoCal at f1.2. Out of 4, there is only one lens has sharpness above 800 with FoCal. Others 3 just around 760-780ish. I ended up keeping the sharpest lens and returned the remaining.
I also ran this lens @ f1.4, 1.8, 2, 2.8, 3.2 and f4. I wrote down the AFMA values on small a note and taped it to the lens hood. I'm not sure if I ever need to stop down to f4 on f1.2 lens, but the datas are there if I ever need it.
Below is my 1st shot after AFMA @ f1.2