I've had problems with flying TWA and obtaining credit from AA, hence I've had numerous discussions with the Platinum desk and the AA desk about this. I've even had flights where I've alternated crediting miles to TW and AA, depending on the length of the flight.

It boils down to the following choice: Do you want more miles, or do you want credit toward AA upgrades? As you point out TWA is more generous with their miles, and these will be converted to AA, so if miles is your game, then fly as a Aviator.

If working toward upgrade certificates you receive when you reach 10,000 miles, then fly as a AAdvantage member, as these miles will count toward the goal of 10,000 miles for 4 500 mile certificates.

If this were my choice in your position, I would choose working toward the upgrade certificates.