For my hike this year of over 1000 miles on the Pacific Crest Trail I brought two, 18L Granite Gear Uberlight sacks with me: one with the eVent bottom and one without. In the one with the eVent bottom I kept clothes and my sleeping bag; in the other, I kept food. These bags got used everyday for three months.
These bags set well inside my backpack side-by-side or stacked one on top of the other.
This review was written in the old system and had content requirements that are different than reviews written today.