They are pretty nifty. I like the way you put your batteries in the one case.
However, I couldn't help but notice how the yellow stood out against the camoflauged back pack. I would try to get something earth-toned or failing that, I would use black.
The yellow would standout just as much if you were out in the hills with that backpack. In other words you wouldn't be seen as low profile, if you didn't want your presence known.
But, you do have a good idea, which I will probably make good use of myself, I will just use a different color.
Bill