How many times it needs to be reminded that the "problems" you descirbing have nothing to do with QC, but the LCD technology itself and the way they attach the panel to iPad housing? Yes you can find better and worse units, but basically all of them have unifirmity/clouding issues to some extent. Basically it's impossible to get 100% flawless LCD in iPad. If you think otherwise, get one and I will prove you're wrong. Apple attach the screen to iPad using force, which makes uniformity problems. Another problem is the backlight itself, which is limited, because Apple is not backlighting the screen on every corners, but instead only one, which makes different hues/tones on the opposite corners of the screen.
People should stop whining about LCD in the iPad basically for two reasons:
1) It's pointless until Apple decides to change manufacturing process
- panels with more backlight LED diodes
- perfected method of attachn the screen to the housing without causing clouding issue
2) Most of the screen imperfections are really invisible in 90% of situations, unless you sit in the completely dark room, put completeley black wallpaper on the whole screen and adjust brightness to max. If you crave to hunt panel defects, you will find them on most of the units 100% guaranteed!