There is an AOC IPS Display available around 8.4K, AOC i2251Fwe.
Now quality wise the BenQ and the Dell model are more or less same but the BenQ offers more features. It comes with all the three input option, VGA, DVI-D and HDMI and also inbuilt speakers whereas the Dell one lacks the HDMI input and speaker. Dell one also 400 bucks cheaper. So, my vote is for the BenQ one.
Regarding size, better pick a better quality 22" display than a lower quality 24" display. At your budget, you will only get 23" or 24" TN panel based Monitors which offer inferior picture quality and viewing angle than their IPS and VA panel based counterparts.