Well, that 24" ASUS is a very good option for you. For $200 I don't think you will find a monitor bigger than 24" at a 2ms response time.
Plus, this monitor has a great contrast and definition, I myself just bought two of them. They used to be $240 and are going for $180 with the coupon, so I would recommend it.
http://www.newegg.com/Product/Product.aspx?Item=N82E16824236153
$179.99 with $20 coupon.