So I went over to see Robert a Value Electronics today after picking up my set yesterday to take a look at the "ton" of sets he has burning in at the showroom for calibration. I went specifically to see what the sets looked like with 5% test patterns up. I looked pretty comical with the black sheet over my head and the sets lol. Anyway I noticed that there is absolutely zero, yes zero, vignetting on all the sets. But what I did notice, after looking very carefully, is about a 4 inch wide band, extremely light, on each side of the set. My guess is that Sony is doing some sort of processing to mask any potential vignetting. Interestingly, it's impossible to see these bands with real content even when you know exactly where they end. This is just a guess on my part but every set has this if you look close enough in a dark environment. I'm not sure if the LG is doing this as well but i'll check the next time he has one in the showroom.
The other thing I noticed is that Cinema Pro and Home has the OLED light set to max and the contrast almost all the way up as default values. Compared to my E6, to my eye, the luminance looks identical to my E6 with OLED light set to 70 and contrast set to 80. That said, and again i'll have to check with my meter, it seems like you have some headroom on the LG to increase the luminance in SDR where on the A1 it's almost maxed out with the default settings.
One disclaimer, the A1 is plenty bright but the point is that it looks like you can adjust the C7 to be brighter which may be a difference. Personally, my E6 with OLED at 100 and Contrast at 80 is way too bright for me even during the day. So this difference is not bad but just interesting given both sets are using the same panel.