Interesting thread. Our main desktop PC in the office has three 22" monitors. I love all the screen real estate. I don't think I could work any other way.
But they are all 8-10 years old running at 1680 X 1050 with DVI connections from two separate aging graphic cards. The monitors are all different brands that Ive accumulated over the years. None of them match exactly, with different support stand designs and slightly different bezel sizes. But they are all at the same height and I've adjusted the brightness and other parameters so they all look the same. This has worked extremely well for us for many years.
But one of them is starting to fail. I think it's a power supply issue. Screen goes black right after it wakes up and has to be power-cycled once or twice to stay on. Anyway, it's hanging on to life for now. But I'm also due for a new PC build this year. So maybe in the spirit of BTD, I'll upgrade both the PC and the monitors. I really like the sharpness of IPS and 4K monitors I've seen. Three 24" 4K IPS would be amazing but pretty expensive.
I'm not a gamer, but I do watch a fair amount of video on that PC. Although it's mainly used for documents, spreadsheets, SketchUp, photo/video editing, some music production, as well as online shopping and financial transactions... often multiple things at the same time, which is where the 3 monitors work well. DW and I do most casual browsing, email, etc on our smartphones.