i think the best cleaner that one could use on a flat panel and that will not leave any marks is demineralized water.
Humidify the microfiber cloth, but don't make it wet, and gently go over the dirty areas and then use a dry microfiber cloth.

it may not be the only one to not leave streaks, but it will cost very little.

Last edited by J. B.; 12/12/11 02:51 PM.
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