Ok let's get the vote in before the deadline, I vote for mrk.
Monochrome is all about texture and form. This image has it spades. I almost expect to touch the screen and feel the rough texture of those seat cushions. The metallic overhead luggage rack offers an interesting contrast and holds in the top of the composition in and the whole thing sits on 'a heavy,' base provided by the shadows thrown by the seats. I initially thought the window could have benefited from a slight local expose adjustment as there is danger of leaving a bright empty space in the centre of the frame but there is very little room for adjustment because if the view through the window gains much more detail there is risk that the outside view would fight with the interior which what the author wanted us to look at.
I'll try and get back later this week with some comments and observations for some of the other images - I've just run outa time this week.