maestromodesto I haven't used the light that much, because I'm very sensitive to PWM/light flickering and the two light options my Dasung model has (blue-ish and orange-ish) also strain my eyes.
As for the actual quality of the frontlight, keep in mind that my model is almost 5 years old and I have no idea what improvements Dasung has possibly implemented since then, but it looks like the frontlight of other eink devices, maybe a bit cheaper, because as devices like the Kindle or Kobo e-readers try to minimize ghosting as much as possible (and have an easier time doing so, because there's no constant updating of the screen unlike an eink screen used as a computer monitor), this effect becomes more pronounced if you turn the light on.
But I'm also the type of person who thinks that having a backlight or frontlight kinda defeats the purpose of an eink screen. Not sure if this answer is what you were looking for 🤷