as far as airtightness goes, for those who question the ability of the box to stay airtight, they sell this stuff that is sort of like liquid rubber paint, which is sold as a way to rubber coat items such as tools and other items which can benefit from a better grip. But anyways take that stuff and paint a little of it into the lid of the boxes, when dry it should form an O-ring like seal in the container.
And i too have issues rationing, i like too just get blazed as far as i can get everytime i have anything, which sucks cause the little doses i have with friends dont really affect me like they would if i went slower.