World has been on the verge of going out of business for 60 years.

I can't speak of the other carriers and to be frank, it's a crap shoot. Of the 3 carriers that Global owns, World is doing the best. We are making money while ATA is bleeding alot of cash and North American is bleeding less. The CEO of Global just resigned (fired?). Pre 9/11, I think most folks would have said it's a no brainer. Go with Airtran, of the three. Now, with high fuel prices???

The one thing I will say is that comparing World to Airtran is compairing apples to oranges. It's a totally different lifestyle. Your spouse (if you have one or thinking of getting one in the future) will determine if you like World. I'd guess that Southern is more like World in this area.

You've asked a hard question to which there is no good answer.