Originally Posted by amiras

If you have eVIPs to burn I'd say use them since you get 12,000 miles for flying a 3,000+ miles in F (A fare) instead of the 3,500 you get for flying J. Another potential benefit might be in case of IRROPS specially going to Asia. You may end up in CX F instead of AA F which is much better. Other than that, I agree, no real reason to upgrade.

Edit: this assumes you are EXP. You can check AA to see what kind of bonus applies to you based on your AA status.