The Avia set-up disk (or one like it) can definitely help improve the picture quality. It can also help to explain the differences in the settings (brightness, picture, contrast). Many TVs are factory set to work well on showroom floors lit with fluorescent lighting. Subsequently, these settings are often too high for the home environment.

Buying a set-up disk is a great investment.

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"Nothin' up my sleeve. . ." --Bullwinkle J. Moose