How to simulate a retina display
I recently purchased a 27 " iMac with a native resolution of 2560 x 1440. Beautiful and crisp but I could not see the tiny text. I was able to simulate a retina display (HiDPI model) on my mac. I was seriously thinking about taking it back and getting the 21" but now its just awesome. This resoulution took care of everything, no more adjustments needed for my browsers, finder menu, it all looks great. Here's how I did it. Here's a link for reference.
osx - How to simulate a retina display (HiDPI mode) in Mac OS X 10.8 Mountain Lion on a non-retina display? - Stack Overflow
Search for, download, and install Apple's free Graphics Tools for Xcode (free Apple Developer account required). Choose the version for your Mac.
Launch Quartz Debug application.
Go to menu: Window ---> UI Resolution.
Check Enable HiDPI display modes.
Quit Quartz Debug.
Open System Preferences.
Select Displays icon.
If using multiple display, select the configuration window on the display you wish to simulate HiDPI mode on.
Under Resolution:, select Scaled radio button.
Find a desired resolution postfixed with (HiDPI) and select it.
Your display is now running in HiDPI mode, simulating a retina display.