I currently use this: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Lots of space for groceries or whatever, and the MOLLE loops give me a place to hang my U-Lock comfortably.

For something smaller, I have this: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Mind I did crack the zipper on the front pocket (the small one on the strap). Not had any other issues, however. The topmost exterior pouches of each fit this first-aid kit nicely.