You can't compare those two monitors. They are using a different panel technology. However, the choice should be obvious... You enjoy playing games with the NVIDIA 3D kit, Asus it is.
Regarding the difference in color. Calibrate it the first thing you do, Windows has a great built in calibrator that is very advanced, considering it's free. And you should be getting pretty good results. A lot of people don't calibrate their monitor, it's a very quick process if you're doing it for free, highly recommend!
Calibrating: Tape or have a white piece of paper next to your monitor covering the bezel, that way you'll be able to quickly fix any blue, red, and green tints. IPS monitors are generally closer to accurate, however - 99% of them still requires calibrating from the user after purchase. However, a TN panel can never get close to an IPS monitor's color, because it's a limitation of the TN technology. Green obviously won't appear red, so it's not bad either. Just a bit washed out look when compared to an IPS.
All the best!