I always imagined using dual 27" screens like that too. However, I have found that I prefer to stack a tall-ish browser window and terminal on the portrait monitor and keep 2+ panes of code on the landscape monitor.
Not here, web pages are virtually always a lot taller than wide. Putting them on a portrait monitor means much less scrolling.
Fair point but you also miss out on features because of responsive design. For example the sidebar on Facebook disappears when I browse it on a monitor in portrait mode.