Good build quality, durable zippers, durable bottom section made entirely of hard plastic, so it can withstand the impact of children dragging it down the stairs relying on the wheels, regardless of how the bag full of books falls from step to step. It is also spacious, but not comfortable to wear due to the trolley. However, you buy it with wheels precisely so that you don't have to carry it with so many books inside, but rather to pull it and let the weight press on the wheels. So it's a good choice, especially at the final price of €33.5 that I found it.