I had 2 screens when I worked in an office and definitely found that my sweet spot, I don't think I could have processed content on a 3rd one. At some point, I shall get a monitor, an external keyboard and a laptop stand so I can have the same set up in my home office. My laptop is fine for a couple of hours at a time but my RSI was a tweaking a bit over the weekend after working at it for 5 hours on Friday.