Personally I prefer multi-monitor setups as, if one monitor goes, you can swap it out easily enough.
This is a great place to go: Zenview multimonitor setups.
https://www.digitaltigers.com/zenview.asp
In particular:
https://www.digitaltigers.com/zenview-apex22h.asp <-- smaller size.
https://www.digitaltigers.com/zenview-apex27.asp <-- nice setup with the 27" monitors.
Now, anyone who has dual monitors already knows that productivity increases by at least double over that of a single monitor. Triple monitors, in my opinion, further increased my productivity. But I really like the 4th monitor because you can have stuff like notes, skype chats, slack chats, and other extranneous items opened in the 4th/top monitor while your productivity takes place across the three mains.