I still love using multiple monitors (I currently dedicate an entire 27" monitor to a single full-screen terminal with tmux as the "window manager"), but it is really nice having the know-how to do the full development cycle from a terminal. I used to be afraid of command-line stuff and I think it really held me back in some ways. Because I used the terminal only when forced to I never could remember how to actually use it beyond the most trivial stuff, which just made it more frustrating when I had to. And I never could find a true tiling window manager on OS X that I liked; tmux works great for that out of the box. I still want to experiment with an xmonad-based workflow on Linux, but I haven't really had a reason to yet.

My job forced me to get over that, and though I can still appreciate a good GUI-based editor I don't feel any need to switch to one anymore.