Best way to clean LCD monitors:
take 2 lens cloths, wet one under the cold tap and wring it out so it's just mildly damp and not wet, clean the screen with it from top to bottom till it looks like you covered the entire surface, then using the other lens cloth go over it drying it straight away, should come up streak/mark free.
I do this on my monitors, never a mark on them, I was told this technique by a guy on the wacom stand at focus on imaging a few years ago, works well. 😉