I'm using this monitor since april for home office and gaming as a main display.
This is not a long time I know, but so far I don't see any burn-in at all.
The firmware does a really good job when is comes to burn-in protection.
According to my research and the manufacturer's specifications, a "burn-in guarantee" should also exist for this product, but only if certain requirements are met. This means that the monitor has "burn-in damage" despite normal use and the countermeasures switched on to prevent the image from burning in.