I was issued one of those 5.11 vests. It's nice but I wouldn't buy one. It's way too hot in the summer because it is double thickness the whole way. Unlike most other similar vests, it has no mesh. The reason it's double thickness is that it allows you to put weapons and other items between the two layers. There velcro in there and various holsters and ammo pouches for it. It doesn't even work real well for hiding a weapon. The weapon seems to make the vest hang low on the gun side (weak hand side) unless you anchor the vest to your belt. (There are snaps inside to allow you to anchor it.)One vest that is great and has lots of pockets but doesn't look threatening is the 5.11 tactical vest (see post above by Moodino)
I suppose you could put your kit between the two layers, with only a little velcro and some handywork. If I were inclined to hide a kit inside a vest, I'd just put some pockets inside a single layer vest. Again, that 5.11 setup is very hot in the summer. Imagine wearing two THICK canvas shirts over top of your normal summer shirt... or wearing a ballistic vest. It's very similar.
If I were making looking for a vest to carry basic survival stuff, it would be a more generic "safari" or "adventure" or "traveller" vest that incorporates a lot of mesh.
Yeah, that too, but that doesn't matter as much on a trail as it does in a mall.that to wear one screams "carrying concealed," or "COP!" or even "WANNA-BE!"