I don't understand the appeal of such a small monitor for such a high price... I currently run a 40" 4K Philips monitor, and while it's not ideal for gaming (only 60hz, a bit of ghosting) I would not trade it for something smaller. Personally I'm waiting for the nVidia BFGDisplays - 65", 4k, 120hz, that's going to be worth spending cash on!
Only problem i have around with using as large a screen as that, same actually go for multi screen setups as well.
is the limited view angle on LCD's.
If you get close enough to a 40" you will see the colour degradation towards the sides.
But that's me nitpicking.
OLED should be fine.
You could also go super big and use a projector.
Reflected light is great