Oh, and for touring, you can use any cheap 29" airline legal case with either the Dahon or the Birdy. We found one of our suitcases on the street. That one is a bit wider than a Samsonite Oyster, and the bike fits very easily. If you get a trailer, you can tow the suitcase behind you with all of your stuff in it. I'll try to post a picture of this. We mostly tour with Ortlieb panniers, though.

The Dahon is much harder to pack. You even have to disassemble the stem if you have a fixed stem bike like the Mu SL.