This is a zero buyer's regret purchase for me! I'm not a gamer, I just needed the best 4K IPS monitor for extended use at a sensible price. I took a gamble and bought the VG289Q for CAD/Office use based on its specs before there were any in depth reviews such as this one. Based on my subjective observations, I think this is an accurate review of what I have found to be an excellent and reliable 4K monitor for work/general purpose use, which is particularly surprising given the price. It looks like Asus have chosen a good IPS panel here. It's all in the review, but some points to emphasise:
flicker-free backlight
good colour accuracy
even backlight brightness distribution
zero dead pixels
IPS panel gives very good viewing angles
blacks are good
three year warranty
superb stand - very solid and adujsts for height/tilt/rotation
not noticed any IPS "glow"
28" size
modest price
After about 500hours of operation there are no issues at all . BTW -if you look closely the Amazon reviews are actually for a mish-mash of similar Asus monitors.