I still carry my basic PSK in a tin, though it's a tobacco tin sized container (quite a bit more volume than an altoids tin), which is just about the right size for a belt pouch or cargo pocket.

The reason I decided on a tin this size is because it's small enough to fit into a cargo pocket, but large enough to carry a water container -- in my case, a couple of rolled up bags with a 1 liter mark on them for use with the water purification tablets. You might be able to cram something like that into an altoids tin, but for all practical purposes you won't have much room for anything else. I really wanted something that had it's own water container available because if I was left with nothing but the kit, it's not easy to find a bowl in nature, and I wanted this to be able to serve as a stand alone kit, not just a supplement to my EDC.

I prefer this to plastic containers because although it's not as water resistant, the tin can be used to boil water in (I've tried it), though not a LOT of water. I realize one can boil water in plastic, but it is more challenging.

I prefer it to soft camera-bag type pouches for the reason stated above, plus it's a bit more water resistant than those pouches.

It's a tradeoff. Plastic containers are more waterproof, and pouches are more comfortable, but IMO metal containers have more uses.

Anyway, I know the odds of me needing to actually survive with nothing but this kit is almost nil. My EDC is pretty well thought out, and if I am going out hiking I will of course be carrying other supplies in addition, plus I try and do due diligence and inform others when I'm out and about. I've found that taking the time to create a well thought out PSK has the side effect of making one less likely to find themselves in a situation in which they need it in the first place... and that's fine with me!