Article: Building a CustoMac: Buyer's Guide January 2013
I have a GTX 560ti running a 27'' Achieva Shimian (same as Catleap)2560x1440 4x HD resolution, they are the same LG Panel used in 27'' iMacs.
They are sold on ebay from korea for around 250-280$ Some say they are actual Apple rejects LCD panels. Mine came in after a 5 days in perfect condition I have 3-4 stuck pixels on the right bottom edge of the screen but I can live with that (they are really at the bottom edge not anywhere important). Other than that, the screen is much easier to look at then the awful 1000$ Dell UltraSharp U2711 that promptly returned because the anti-glare coating on those display makes graphics work almost impossible.
The only caveats with this cheap display is that you need to use a graphics card for them to work in OSX, they won't work with HD4000/HD3000.
Still, for the price I highly recommend this monitor, it so awesome to have full two-page apps side by side and the graphics and text are tack sharp. You can always use Mission control and have multiple virtual display if you so desire. I think one single monitor of this size and resolution is better than 2x24 inch 1080P monitor any day of the week. I would never go back to using a monitor with only 1080 resolution Having full page apps with almost no need to scroll down ever is just too awesome. And if you guys wonder, under windows with this video card, I still can play most recent games at the native resolution of the monitor with decent framerates and graphics effects maxed out in most cases, the increase resolutions makes jaggies a thing of the past. ;-)