I think all of them are good with just very slight differences. All of them have the 1680 X 1050 native resolution with both DVI and VGA terminals and a claimed contrast ratio of 3000:1. The Samsung has the fastest response time of 2ms but it's also the most expensive at around 16T. The others have 5ms which is not bad at all for fast moving scenes. At the 13.5T price point, I'd prefer the MAG brand over ASUS For 1T more, there's LG. For about 15T I'd go for the ACER brand. The AOC is the cheapest at 12.9T. These are all Villman prices. Really, I'm still mulling my options too. I guess it now just boils down to ergonomics.
I've narrowed down my choices to LG, MAG and Samsung. I'd have to save up some more if I decide to get the Samsung.
I am using a conventional 15" LCD Samsung Syncmaster 153V now so I may be biased towards it as I've not had any problems with it over the last 2 years, turning 3 this July.