DxOMark has completed their review of the 85mm G Master paired with the a7R II. The G Master was compared directly against the 85mm f/1.4 Zeiss Otus and the 85mm f/1.4 Nikon. The Sony scored 49 beating the Zeiss at 48 and the Nikon was left far behind at 42.
They write, "When tested on the full-frame 42-Mpix Sony α7R II body, the new 85mm achieved an excellent overall score of 49 (2nd place in the DxOMark lens database). Individual metrics were of course very high, with the lens attaining outstanding results for sharpness and control of distortion, lateral chromatic aberration, and vignetting.
"Optimum performance across the image field is achieved at f/5.6, but performance is also excellent when opened up one or two stops." The review continues, "Of particular interest to users is the exceptionally low lateral chromatic aberration: images look very clean, even shot wide open."
See the full review at DxOMark.com.