A duffle is the most forgiving bag you can travel with. No rigid frame means it takes whatever shape the space allows — under a seat, in a car boot, squeezed into a full overhead locker — and it packs flat when you're not using it.
Ours are sized around two trips: a cabin duffle cut to fit standard carry-on limits, and a larger weekender for three or four days without checking a bag. Both use reinforced base panels and heavy-gauge zips, because a duffle takes its weight through the bottom seam and that's where cheap ones fail first.
The fabric wipes clean, which matters more than it sounds if you've ever put a bag down on an airport floor. Pair one with packing cubes and the main downside of a duffle — everything settling into one pile — stops being a problem.
