First there's nothing to see approaching HKG, unlike the old Kai Tak. All smogged up. In winter, it's late and dark.

During the flight, it depends on season. For CO99, during winter time, it's mostly darkness, though there's a few hours of daylight over southern Russia, southern Mongolia, and China. The sun is weak, and you get sunrise on left side, sunset on the right. I've never flown it in the summer, but I think I'd probably stick to the east side for the longer daylight southbound from N. Pole to Hong Kong. East meaning left (ABC) side of the plane. But for the first few hours going up through Canada, left side will face the sun.

For the return, CO98 is mostly an easterly flight. So take left side (ABC) to be on the North (cool) side. To see Central Hong Kong through the smog, you'll need to be on the right side, for normal departure.

You may already have seen it, but these are pictures I took on CO99 from 44L and CO98 from 44A, last October/November:

http://rkkwan.zenfolio.com/p476976649/