And yeah, the containers do seem to be waterproof so far. I closed one up and put it in a cup of water for a couple days and it didn't leak. As long as that 'O' ring stays good you should be okay. Don't leave it sit out in the sun, don't expose it to harsh chemicals, don't expose it to ozone (just in case the seal actually has rubber in it - ozone destroys rubber) and it should last quite awhile.