If, like me, you often take short trips where you want everything in one backpack, then this backpack is for you. I was actually a bit skeptical that it really was a vacuum backpack - until I tried it. It's not just about compressing the contents and tightening the straps. There is actually a special compartment with an airtight zipper and a one-way valve that allows you to create true vacuum compression. I tested with a large, bulky dressing gown, and it was barely thicker than a couple of sweaters. Together with compression packing cubes, this backpack can reduce the volume of your clothes by half or even two-thirds, giving you more space for what cannot be compressed.
Plus, the laptop compartment has a TSA-certified lock, which is a nice bonus (although I'd say it's already one of the hardest compartments for a thief to access, unless you leave the backpack unattended). Bought one for myself and one for my partner ;)