As much as the positive things said about B6 are true most of the time, they all lose sight of the question you posed: Is it worth it if the fare on AA is higher? If the fare is nominally higher....I don't think its worth trying B6, particularly if you know your miles will be useable for future travel on AA.
In that case, I would stick with AA in your case, just as in my case I would stick with B6 (because thats where my current stash of points is.)
The niceness/benefits of B6 are not really that special at the end of the day.