Be careful about refresh rates! Personal experience... I have vertigo issues that come and go, long history from a young age. I had used dual monitors for a few years and didn't really have any issues because they were both 60hz. At one point I swapped out a 4:3 for another 16:9...but that was a tv/monitor at 50Hz default. I never thought about it. A year or so later my setup moved to a new house and different lighting/less natural light. I began to suffer from game play induced vertigo, sometimes very easily. The issue... the 50Hz on my left, the 60Hz OC'd at 75 in front.
The answer was simple... set both to 60Hz. Majority of game induced vertigo eliminated. I still get set off by crapping florescent lights at work and too...