Get anything with a nice native resolution for the size of the screen, at LEAST 8 ms response time and at the LEAST around 700-1000:1 contrast ratio (I would assume 500:1 at that size would degrade badly). Of those models (I have not looked at them kind of busy atm) I would say get the Acer since they are known for their good products, I would not get a refurbished one, and I only have seen the Olevia's at my office depot store and what I have seen makes me want to throw them in the trash, the ones we have look like crap.
Anyways sorry I don't have more time to check out the models for ya.
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