Ah, right, rust. I hadn't considered that part - was only thinking of how the case could harm the cigars, not the other way around. There is already some rust on the outside, but looks like only a bit at a seam on the inside. Think I'll go with it, and if it seems to get worse over time I'll just fall back on a coolidor instead. Now to get the other supplies...

Many thanks for the input, everyone.