Well, my samsung just died on me after a little over 2 years. Warranty was only 1 year.
I just bought an Asus, and now I am unhappy that I could have gotten an LED monitor for $20 more. I didn't even look at them because I figured they would be way expensive. Dumb.
And yeah if you want Samsung, at least get a 24". 21.5 is small.
Newegg.com - SAMSUNG S24A300B High Glossy Black 24" 5ms Full HD LED BackLight LCD Monitor 250 cd/m2 DCR 1,000,000:1 (1,000:1)
You could get an Asus of the same size for $200 if you wanted to spend less.
But I would bump up to this for $20 more:
Newegg.com - SAMSUNG BX2431 Glossy Black 24" 2ms LED BackLight LCD Monitor Slim Design 250cd/m2 DCR 5,000,000:1 (1,000:1)
Better response time, better contrast ration, and has hdmi ports instead of just DVI.