This book bag is amazing! Usually my daughter's bookbags fall apart after a few months and I end up buying 3 or more bookbags a year (she carries a lot in her bookbags, so they just don't make it). Her other book bag's wheels would get stuck and wear away. Other times the zippers break off and the material eventually rips.
This book bag is still in great shape after nearly everyday use (part time in the summer). I think this one is finally going to survive. It's very well designed and she has no problem rolling it, whereas the others would easy get off balance and twist when rolling quickly or down stairs. All of the zippers are still intact, it's very strong and there's nothing to get caught it the wheel. Plus the bottom material protects it from wearing away when dragging.