Biggest selling point to 21:9 to me is it's virtually the same as the Cinemascope theatrical format. Cinemascope widescreen with no black bars. That 34 inch model has me seriously intrigued. It looks like it would be better than adding a second 24" 16:9 screen.
Very good price, I wish we had those prices available here.
I looked at this monitor when choosing a monitor for myself recently, I ended up going with a 27" 1920/1080 display but at 144Hz. It dominated the IPS panels around it when it came to fluid animation and instantaneous response (gaming) but wasn't quite as good in color accuracy (black). I wasn't a big fan of the ultrawide, it was hard to see things honestly and I'd probably get a couple of Dell Ultrasharps (almost no bezel for side by side use) for that resolution instead.. and have much more viewing area.