Had an AOC monitor for about 3 years. It had 2 dead pixels which appeared the first time I turned it on. I've since given it away, but no new ones since then. Incidentally, I was trying to show my friend where they were, but couldn't find it; we had to use a black screen to see the dead pixels.
Now using an Amptron (the company I work for) monitor. Been using it for about a year. No dead pixels, although one section of the backlight is slightly dented or something (the light is inconsistent there), but I don't mind because it's only visible at certain brightnesses.
My knowledge is that dead pixels don't really appear once the little transistors have had an opportunity to fully warm up -- any pixels that haven't burned out yet probably won't.
Chuck Hsiao
Amptron