Think Kalniel's nailed it. Been very impressed with Acer's monitors for a while now from a technical perspective, which is what really matters, but their stands are almost always horrible.
The X34 is possibly the only exception, which I actually think looks quite good aside from the little red box and tacky underglow... I could be the only person that still cares, but I'd still like to see 3D Vision support too and >=120Hz refresh; aside from that, the X34 has everything I really want -- it's damn-near perfect.
My only hesitation is forking out £1000 now for a 1440p monitor (even if it is 21:9) when 2160p is already becoming mainstream. I'd much rather pay more for 2160p 21:9 -- even if I end up running games at 1440p on it to begin with -- and sit comfortably in the knowledge that I won't upgrade for another 5+ years. Equally, I'd be a lot less reluctant to snap up an X34 right now if it was a few hundred pounds cheaper.
£1000 is a bloody big sum of money to drop on a monitor, in that bracket I'd want it to be perfect.