I don't know, for a big monitor I think curved might actually be nice. Hard to tell though, I'd really have to experience it for myself to decide. I'm thinking like a curved 32" 4k would probably be half decent. With 3 monitors you would place them in a curved configuration anyway.
We just got all our 4k monitors at work.

The new desks did not come in though. Can't wait to set those up. We've been asking for more pixel real estate for so long so it's nice to see it. My only complaint is they went with 27" so the text etc is kinda small. Lot of the stuff you can't scale either, as it's X11, Citrix etc.