This is probably my favorite lens I've ever owned. An almost-perfect portrait lens, and on the GFX100S, just magical results. Have used it on relaxed portrait shoots and on fast-paced big-budget advertising jobs, and images made on this lens are always heroes. I won't even say the autofocus is slow... it isn't. Maybe not the lightening speed of some DSLR lenses, but far more responsive and accurate than my 85 was on my Canon gear.
I own, Canon 5D Mark IF, Canon EOS R and was went ahead with the purchase of GFX 50R and this lens with EF adaptor. WOW when I take pictures with this one, the portraits are just amazing. Love the bokeh. Beautiful portraits. Buy the combo and get amazed with the quality.
Awesome image quality!