This is an interesting point about the 80" screen size and the viewing angle issues for many LCD's: (taken from HDJ forums):
With the picture paused, moving just slightly off center caused flesh tones to pale and contrast to weaken. At a 9’ viewing distance, moving about 1.5’ to the side caused a noticeable degradation. In fact, because of the sheer size of the screen, even if you sit dead center you may still see some side effects of off axis angles near the screen edges. I saw that the edges became just barely pale at a 9-10’ distance, so color was just slightly richer in the middle of the screen than along the outer quarters of the screen. Sitting farther away will diminish or eliminate the effect, though that is not a very good compromise.