I went the route of getting a 48" samsung 4k/60hz tv's for around $620/ea a few years ago during black friday sales, which I love using now as a giant displays. This was going from 6x 24" in a row to 3x of these, basically giving me the same wrap dimensions, but as though I added another 6x double high for a full 11520x2160 framebuffer. I thought 55" might have been too big at the time, but I almost wish I had just gone with them now.
A month or so ago I saw walmart selling a 55" curved 4k/60hz lcd from Sceptre for $350 that is a steal as long as it's roughly the same quality.
The only downside I've found is the displays don't dpms power-down, so they'll go into screensaver mode and stay on until you power them off. Which in turn triggers pretty much every linux desktop to freak out and do weird things when it loses all of its displays, so most time I just leave them on with their screensaver. Last time I ran into someone with an actual samsung 30" 4k "monitor", it did the same thing, so caveat emptor.
-mb