[stoppingdown]

I own two LowePro backpacks for trips — they contain all my gear, with the exception of specialty lenses (vintage stuff with adapters), that is 99% of my usual activity. I'm perfectly fine with them.
Now I need to increment short walks near home because I need to lose extra weight and I need a very small backpack to carry along just a couple of essential zooms (18-50mm + 70-200mm) plus bodies. In terms of size, 25x~20cm (inner) would be fine. Searching on Amazon and other places I'm finding lots of good and cheap stuff, but considerably larger.
My only strict requirements other than size are weight (but should come by itself), decent quality (i.e. don't break after a few years) and rain protection.

Suggestions welcome.