I personally think that 24.5", 1080p isn't really ideal for gaming.
You're not getting much HEIGHT, and many games don't run great on triple monitors.
*Personally, I think the best compromise is to get a 3440x1440 screen. That's limited to 100Hz AFAIK, but if you use GSYNC (NVidia) or Freesync (AMD) you get a smoother gaming experience.
240Hz is going to be problematic for a few reasons including how to avoid SCREEN TEARING in games. Some will be okay with VSYNC OFF, but many won't be.
*Since you have an NVidia GTX1080 I would consider the Asus or Acer 34"/35" (see pcpartpicker), GSYNC, ultrawide.
Again, 21:9 is wider than 16:9 but not as wide as a TRIPLE MONITOR setup. If you want a wider gaming experience than 16x9 I think 21x9...