Single or dual monitors?

Thanks for chiming in. I started doubting the one-screen solution, but then I saw this: https://youtu.be/PVztGCrZoZY
In the video, his setup looks exactly like how I was imagining my work desk. But if I can work with this resolution? I don’t know … and how can it be tested with Cubase before buying the monitor and bringing it home?

Because I don’t want to be stuck with a monitor setup that I later find is not optimal I’m now looking at other computers than iMacs … Mac Mini looks quite interesting.

I’m currently on MacBook Pro 15" with additional (old) Dell 20". It kind of works, but I’m 48 and my eyes are changing, so there’s that as well.