I've been using a typical Tumi briefcase for years, but recently bought a Tumi Alpha Sport Duffel for travel. It holds a ton of stuff and still fits under the seat. In Winter it is nice to put my coat, hat and gloves in it once I get to the airport. On overnight trips, it is the only bag I need. For multi-day trips I also take my Rimowa Topas. Together, they offer a lot of flexibility.

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