I don't do animations, but for my part, always use the User settings.  Check each and every cranny on the Render Settings screen and get the most AA for your time spent.  Most of the presets are good for one things but bad for another.  Make a User setting that only takes good part and un-checks stuff you don't need.  An example, Broadcast uses good settings for the AA, but turns on Texture AA.  Most renders don't need that. 

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