[Off-topic discussion deleted by Moderator.]
I would say it's very difficult to consider everything being equal.
As far as upgrades goes, your home base, elite status, routes (domestic vs. international), destinations and seasonal demands all play important roles. Without knowing the specifics, I doubt any savvy FTers can give your any tailored advice.
Last edited by lin821; Jan 10, 2010 at 3:47 pm
Reason: To remove off-topic discussion. OP fixing a typo