DPI makes a slight difference. The Samsung I posted above, (the 940BF) has a .26 DPI as opposed to the viewsonic .29. However, I just checked the manf site and the samsung is only a 4 ms while the viewsonic vx922 is a 2 ms.
Check my post^. I attached a number of reviews for both the viewsonic and the samsung. I am still undecided between them. I am leaning towards viewsonic but both are apparently fantastic gaming monitors (and both are $400 canadian, US prices check newegg) and decent for everything else. One reason the reviews don't give really high scores is that almost all of them were posted when the monitors were at higher price points and as such they indicate that the monitors are over-priced for what you get. As they have dropped in price, they would likely get higher scores now. Also the viewsonic for example loses points on reviews for not having any lateral tilt. To people that don't care about that (gamers for example. In my office its a handy feature so that I can swing my monitor left or right to show a co-worker something. When I am at home gaming, I'm to busy to be moving left or right!). As such the review should be about picture quality (Which both get good reviews on), and ghosting which both excel at preventing due to low ms.