Maybe a Jack Wolfskin backpack.

​

I can't speak for any of their current lineup, but I have one of their older backpacks, bought in 2008. It's seen me through 8 years of college, lugging around 20~kg of laptops, books & groceries daily. It was regularily stuffed to bulging point, has seen a fair chunk of Europe and was just generally abused.

​

All the zippers, buckles, straps and mesh pouches are still intact and working. The fabric is a bit threadbare but it still works. I've relegated it to be my climbing gear bag since I've got a Kriega backpack even though the Kriega isn't as nice quality but it's way more comfortable on the motorcycle.