Most discussion on compression cubes means the kind with double zippers. I've found vacuum compression bags to be good for one thing only, a down parka or knee-length coat. I only tried the vacuum-type bag one time, I worried it would rip. I would use the vacuum-type packet for winter travel and would be very slow and careful in pressing out the air. Not so with the Eagle Creek Specter Techs. They are very lightweight and strong, I've used them quite a bit and they're holding up well.