The volume (30 liters) is enormous and can be, thanks to the use of ideal form, especially for books and writing materials. Who when loading it (as I regularly) is exaggerating but soon realize that the carrying system has comfort limits (no reinforcement formwork such as when hiking backpacks). In normal use, the Berkeley can thanks to the wide strap but comfortable to wear.
The zippers on my model are fully nickel or chrome plated. So how good are the new Zipper I can not judge.
The build quality is great. After 11 years of a seam is now wiped out on the ground, so I need a new slow. Otherwise me a good piece never let down has (maybe I'll just as easily sew ...).