YMMV

YMMV, acronym. stands for Your Mileage May Vary, used as a phrase to infer that results or experiences may differ from person to person in a given situation, especially used in social and other subjective situations.
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Addendum: The origin of this term is from gasoline and automaker legalese when it refers to the generally stated MPG for a car. It was adapted for use by message board users often when giving advice or their own opinion, whether or not they use a personal experience to back up their point. It essentially is used as a shorthand for "this is my experience/opinion, but just a warning; it may end up differently for you".