Turned out to be not so nice.

I boarded in Tosu and there was a couple with a lap child occupying my carefully selected window seat and the one next to it. I sat on the aisle two rows back. I decided to be a nice guy for a change. The little girl did come back to offer me some grapes as a consolation, so that helped. I just sat in my seat for the whole trip. There were people going up and down the aisle constantly.

The view was nice, but the view from the Kurokawa Onsen to Aso bus was better. Yufuin station was nuts. Lots of foreigners pushing around really big spinners. I do mean "pushing" for several of them whose luggage was more massive than their body.