It is not uncommon for some Korean manufacturers to cheap out on flicker free backlight system....
Then, instead of using direct current to control the backlight voltage like proper PWM free monitors do, they just control the digital white level.
"As a result, contrast ratio is destroyed and it is hard to achieve a satisfactory setup."
better to wait for verification, maybe there is some info on Korean forums?
I saw this on the Monoprice 27" 2560x1440 monitor - It was pretty bad. Amazon should protect you on the return though. I would also make sure and use a good credit card that has a good return policy like Discover.