I'm using triple 1920x1200 (16:10, slightly more vertical than the common 16:9) with a 1080ti. Fov at 150. Distances set to max, all eye candy off it reaches 60 fps almost all the time.
I would have preferred 4:3, but those were no longer available at any reasonable price (there's still one or two on the market...). Today there's some extremely wide ones that are probably the better choice than three.
Be careful with using different iterfaces to the screens (e.g. 2x display port and 1x dvi). At least on previous-gen AMD the screens didn't sync: One screen shows two half frames. No idea which gfx cards are affected, when switching to Nvidia I also switched to pure display port.
Curved screens probably don't make any sense like it doesn't make any sense to set them up at an angle. AH renders a projection to a flat planar surface (like all games do, commercial flight simulators do some magic to solve this). To view that correctly the screens have to be perfectly flat aligned. This means the further to the side something is, the further from 90deg the screen needs to be looked at. And this means that for just a little more field of view an increasing amount of screen space and pixels to be filled are needed. And the screen still needs to look pretty when look at high angle.
Advantages are good peripheral vision. And zoom: The max zoom level seems to be determined by screen width. This seems to allow the center screen to appear zoomed in pretty far (compared to songle-screen).
