The IPS screen on the HP will probably give you the better image and color. However, the Asus is most likely built a bit better. Those consumer displays from HP, dell, etc are pretty junky. Asus makes a pretty nice display at a lower cost. The higher end professional HP, Dell, etc displays are pretty nice though. I swear by the Dell professional ones.
Between the two, I'd take the ASUS. It looks like you are on a Canada site. Would you be willing to look at Newegg? They have tons of deals on displays.http://www.newegg.ca/Product/Product.aspx?Item=N82E16824236049
also the ASUS above here is a better deal:http://www.newegg.ca/Product/Product.aspx?Item=N82E16824236112