They look pretty decent, although I would rather put together a rig with workstation-class parts, myself... and that becomes even more attractive if you don't need all the redundancies built into them and can just buy a regular computer.
I personally bought an Iiyama prolite-xb2779qs-1, which is their flagship 1440p IPS monitor for Europe. I'm actually now trying to sell it, because although I love the size and resolution, I find myself using my 120Hz monitor more. The other thing, that's a big sticking point for me, is that IPS actually has worse colors than TN does when the monitor's brightness is all the way to low, like you would use when gaming at night.
Long story short, great monitor, not for me, but I have experience with it and with both high- and low- end TN panels and can answer questions for you.
What are you going to be using this monitor for?