Just had a very helpful and nice agent suggest that 4K was 'preferred by many ff's', but I went with what I'd learnt from here and booked 2K instead.

Row 1 is too close to the galley, that I know. 4A has a toilet close behind, so no thanks.

Anyone been in 4K? How does that compare to 2K?

I'm on a day-time flight from LHR - IAD in Aug - starboard side should have a nice view down on Greenland, and down the eastern coast, shouldn't it?

Cheers!