hmm, if this is a game sprite then u better use the A one because the light antialias pixels wont look so good against a dark background, unless you want him to have a glowing aura.
I'd say B. It looks nicer.
But then again, the difference is insignificant compared to the slower speed you'll feel in MMF. So, I'd go without anti-aliasing for that sprite, if it is a MMF sprite.
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