I thought I'd ask the experts here what rationale they use to decide whether to switch FF programs from one domestic carrier to another. When have you made the switch, and was it a good idea or a bad idea?

I've accumulated silver status and about 70,000 miles on United, but the lure of Continental -- plenty of flights from Newark to Europe and Newark to LA/SF (my chief interest), as well as the unlimited space-available domestic upgrades, AND newer planes on the routes I fly -- has me thinking that with the start of the new year, I might as well switch carriers. On the other hand, United has a much better international alliance, and I've already earned a bunch of miles on United and have a MP credit card.

Any advice in this particular case?

Also, any good stories about the good and the bad of switching programs?

I recommend Northwest because your status and miles are just as good on CO, and their domestic route is great.

???

Daniels-

Welcome to Flyertalk. You should know that CO�s transcon flights in coach are the most uncomfortable way to fly ever invented. They use all narrow body aircraft, mostly 737s with an occasional 757. Seat pitch is terrible � you will be sucking your kneecaps for 5 hours. With the small planes, there aren�t as many first class seats to upgrade to. In short, UA or AA is much better.

Use the airline that works best for you. It sounds like CO is your best choice for flight options. As for the comfort level on their planes, how do they work for you? If you're 5'6" and thin maybe you don't get a lot of extra benefit from AA's extra room. It all depends...