For professional use, I definitely need two monitors. At home, I have two monitors. One's a high latency "pretty image" I use when I watch stuff. My main is the lowest latency monitor I could find, which I use for gaming.
I don't like multitasking, like watching something and doing something else. It's just depriving both experiences. I focus on doing one thing. So don't use it to deprive a series watching experience. I use mine to keep track of more stuff, depending on what I do.