As already stated, most of those pre-made kits are a joke - why not start out with figuring out what you theoretically need first, and let that dictate what size container you need? Starting with the (very small) container, and limiting yourself to what you can fit in it, always seemed a little bass-ackwards to me. Or, more of an academic exercise for people to geek about on survival forums, than a kit that actually reflects reality.
"A gentleman is someone who knows how to play the accordion, but doesn't." - Tom Waits