I've just done the distortion tests ... place your bets .... ;-)
I bet on very odd pincushion distortion from wide angle already, getting stronger into the zoom range? :ph34r:
Saw one of these today, a friend apparently has one and he uses it on his A7II.
For those who might be interested, it does not cover anything like FF sensor at any focal range. So, it's not another 10-18/4. Maybe removing the rear baffle may change things but from the amount of vignette I saw, I wouldn't bet on it.
Just for the fun of it ... ;-)
Yikes. Post-correction resolution must suffer a bit, no?