To be honest i went from a 27" 1080p 60Hz Flat Screen to a 34" Curved 1440p 120Hz (1900R) monitor and as much as it pains me to say i don't think it was worth the AUD$1600 (about USD $1100) that i paid for it - Alienware AW3418DW.
Immersion into gaming happens on any sized screen, just a fraction quicker on a larger screen, including a curved screen but in hindsight i wish i had bought a 4K monitor for my rig given how potent it is. I don't think you need to go curved for the sake of it, once you use it for a little while you dont even notice the curve....
If i had two of these screens i would think the immersion would be much greater as i would feel surrounded....