I too use a single 1080p monitor. I find that, for me, the benefits of multiple monitors aren't really there.

I tried it for a while but I find virtual desktops cover my multi-tasking needs just fine.

When I had multiple displays the context switching involved in moving my head and focusing on the other displays wasn't great.

I guess if I was a designer it would make more sense but for coding what I have now works fine.