Quad backpack... there are cheap quad backpacks, there are photo backpacks and there are expensive quad backpacks. Currently, I own a quad backpack that belongs to the last category: Torvol Quad Pitstop Pro. After using it for 3 months, it's time for a review. It's not an ultimate quad backpack, but probably it is the best quad backpack on the market right. Too bad it's so bloody expensive...