This issue is present via ACR, SilkyPix and JPEG. SilkyPix and JPEG produce such impaire sharpness that that the evidence is less obvious, but it is still there.
This example is of the same scene with same lens, same RAW processing and sharpening, but varies in reproduction ratio slightly, and in color temperature of the lighting. The artifacting is still present, but in some areas (doll’s hair), the difference is night and day. As of this writing, the reason(s) for this difference are entirely unclear, but what I found in field shooting the X-Pro1 was that some images look good, and others look truly awful.