I actually have the majority of my Frequent Flier miles through Northwest. While I can understand some of the angst against them, I honestly don't think they are any worse than the rest of the airlines. They all pretty much stink. Here's a rough estimate of my miles: Northwest: 45,000 US Airways: 35,000 Delta: 30,000 Midwest: 25,000 Continental: 25,000 Airtran: they use 'credits' or something like that, not miles. My guess is around 20,000 miles. United: 20,000 American: 15,000 Frontier: 12,000 Southwest: 5,000 Mexicana: 2,000 All of these were accumulated in the last 3 years. I feel that this gives me a little bit of experience with the state of air travel as it is today. All said, I would still go for the cheapest flight, regardless of airline - unless Midwest or Frontier were within $20 of the cheapest flight. Midwest and Frontier are by far #1 in my book. Airtran comes right behind them, then Northwest and Continental. My Mexicana miles were pretty nice actually - they gave me a FREE meal which was better than anything I've ever paid for from an American airline. Trust me - having a 100% travel job is an easy way to get sick of airlines, any and all of them. One week you could be pissed off about cancellations or delays with one airline, next week it is a problem with customer service with another airline. Might as well spin the wheel with the cheapest option.