its a lottery
I got my 12' 11 inch MBA and the screen was yellow and dull compared to my 11' 13 inch MBA. It had the AOU screen... called APple and they sent me a new MBA and it has the LG. The LG screen is heads and shoulders better than the AOU and I'm very happy with it. I'm confident that LG and Samsung both make excellent screens, I'm sure that AOU can as well... it's just on the whole Samsung probably has better QC and statistically less of a chance of getting a bum screen.
I got my 12' 11 inch MBA and the screen was yellow and dull compared to my 11' 13 inch MBA. It had the AOU screen... called APple and they sent me a new MBA and it has the LG. The LG screen is heads and shoulders better than the AOU and I'm very happy with it. I'm confident that LG and Samsung both make excellent screens, I'm sure that AOU can as well... it's just on the whole Samsung probably has better QC and statistically less of a chance of getting a bum screen.