I game on one virtual representation of my real monitor at 4k60hz, and one entirely virtual monitor at 4k120hz. When I am playing a game my sister wants to watch, I play it on the screen that also exists in real life. When I am playing just for me, I play it on the 120hz screen. They are one on top of each other, at the touch of a button they swap exact places with each other. I put the one I'm playing on currently at the bottom.
The main reason I do top/bottom is because the screens are quite large. About the equivalent of sitting a foot away from my real 55 inch TV, but the screens are 20 feet away for eye comfort. So I can effectively only see one screen at a time as they each nearly fill my vision. As big as they can be without having to turn my neck to see parts of them. The top monitor is tilted down towards me, and basically on the roof. Oh, I should mention I generally play from a recliner when playing desktop games, so even the lower monitor is tilted down to face me.
When I want to play something in ultra-wide, the virtual screen can be set to 5740x1080 at 120hz(equal to 3 1080p screens side by side, but as one screen, flat or curved to any degree you want), but for the most part anything that works in ultra-wide works in VR, and full VR is likely gonna be the better option.
Although most of the time I'm playing full VR games and standing to play them. No apparent screens there, just living in the game.