I wish this lens was available for E-mount. I understand fisheye lenses are an extremely niche but it would still be so cool for things like event photography
Corner sharpness is actually consistent, the issue is shallow DOF when up close. How it behaves is quite funny on a fisheye lens, as the field of view is curved, but the DOF is not. A better comparison would be to somehow fill the frame of the lens from at least a medium distance.
I think this lens could be a workhorse for real estate photographers who do 360°-tours. You only have to do like 3 pictures in one row which you have to stitch together for a sharp image