Flew LAX-PVG-LAX on the 787 and tried 6L outbound and 5L inbound.
6L I found to be excellent, plenty of space, good for sleeping, no connected seat issues, no noise from the bathroom. Really liked the reverse position, seemed very private. Only complaint, was it was the worst business class service I ever had. Once the main meal was served I expected to get a drink refill within some time period but I think they completely forgot, rang the bell, which I never do, but they did not respond. Finally after 20 minutes someone from coach came by and helped. The dessert was never delivered to the mini cabin, I went and asked 30 minutes after the dinner was cleared and it seems they just forgot about us. I went to the walkup bar for drink refills after that because no one every came through to checkup.
5L was ok, the space was a lot tighter around the shoulder when upright compared to 6L, I am only 5' 7" and average size. When in bed mode it was fine, I tent to be a side sleeper on planes. The seat is very private and the service was excellent.
I'm not sure if the mini cabin tends to get ignored or I just got unlucky but I'd still choose 6L in the future.
My next trip LAX-HND 1H was the only unconnected seat still opened so I grabbed it. Any thoughts if I should take 2A or any other middle row instead?