1) I dislike multi-monitor for gaming:
- gap between monitors
- image is warped (NVidia has a fix but only for newer games with a plugin using GTX1000 series)
- monitors usually FURTHER AWAY due to having side monitors (I sit TWO FEET from my 27", 2560x1440 which is about perfect IMO)
- I prefer 2560x1440, but that's a lot of pixels for three monitors unless you have a very good GPU (I believe you get about HALF the FPS compared to a single monitor.)
2) *A single 3440x1440, GSYNC panel (plus good NVidia GPU like GTX1070) is one of the best ways to go
- with a screen this wide, and sitting at the proper distance (roughly 2->2.5 feet away) you do NOT want to turn your head any further to the left or right
- with 3x large screens you'll end up having to move the monitors FURTHER AWAY which then defeats a lot of the benefit of getting large monitors.
3) If you really need more WORK (not gaming) real estate then consider getting two monitors that you can ROTATE so that they match the HEIGHT now (i.e. 1920x1080 24" ?). You can CALCULATE that once you know the size and ratio of the main monitor.
Summary:
- avoid multi-monitors for gaming
- GSYNC, 3440x1440 100Hz, IPS is considered IDEAL by many people
(Freesync is cheaper, however there is no AMD card I would currently buy at this budget level. The cheapest Freesync monitor I like is $550USD which is a 27", IPS, 144Hz monitor. A lot of people would be happy with an RX-480 and that monitor, but I want a more powerful GPU such as GTX1070 or GTX1080 so Freesync is simply not an option for me)
Having said that, I'm waiting for prices on monitors to drop. I'm okay with my 27", 2560x1440, IPS, 60Hz panel for now. I'll also probably hold off for HDR monitors.
Other:
Ultrawide has its caveats too. Mostly the fact that you'll get BLACK BARS on the left and right for unsupported content, or for content that is too warped so you set it back to 16:9 ratio.
I really wanted an ultrawide, 3440x1440 however after doing a lot of research I decided against it mainly due to the black bar issue, so for now I consider 2560x1440 27" up to 32" to be ideal. That may not bother you though.