I think the Acer X34P is a better buy anyhow...who wants 1080P on an Ultrawide!?
And if they do...why?*
If your graphics isn't up to running 1440P then just create a custom 2560x1080 profile and you can run 1440 when you have the graphical grunt further on down the line.
*Unless of course £500 is your absolute budgetary limit.
In which case I'd say it was well worth while saving up for the 1440P UW.
Wasn't a purchase for I but as I say, with it going up over night by 100 quid the Mrs will have to stick with her current Screen.