I think the more subdued and inconspicuous is best.

Black/Gun metal is best for a safe. Again, it shouldn't attract attention. A cover for the dials is a great idea, not only to hide the fact its a safe, but also because I feel the dial dates the box. Honestly, I feel the dials detract from the design and appear out of date.

I like the idea of a black box and Eugene's idea for a cover for the dials. The cover could just large enough to cover the dials and it could be magnetic so it is easy to remove. The cover could also be black with a clear slot/pocket on the front that you could add your favorite color or a decorative image. My kids have soccer cleats that can be color coordinated by inserting different colored inserts into a small accent pocket on the side of the cleat. The cleats come with 4-5 different colored inserts to choose from. I think something like this would be better than adding an accent color to the box itself.

How about a cover for the dials? Adds to the stealth and makes it look like a normal box at first glance.

Perhaps a padded inside would be good as well? It could be lined with felt or silicon rubber to decrease rattling sounds when moved.

ditto, i agree w/everybody :)

All black so it's fully concealed

Colors...AWESOME!!!

I voted for this color, but I really don't think any color would offer enough concealment for added security. A determined would-be thief will find the location of your valuables; it's more a matter of deterrence through difficulty,delay,and the potential of being caught. If the cable is hard to cut,if the lid is hard to pry open,and if a loud, hard-to-silence-without-the-code alarm is incorporated,then the potential concealment provided through color selection becomes much less of an issue. With that in mind, I think a very effective sales strategy might be to license this and offer it in school colors and/or with school logos.

Black absorbs all aspects of light. While white reveals, black conceals

Black is least likely to be noticed. Best choice.