You guys are so going to get killed in the streets with that shoot me vest attire
Concealment was a requirement, so I'd say we need to define that a bit more... Are you talking not have visible items AND blend into your surroundings or are we just good withy folks not directly seeing your stuff, but we are OK with sticking out a bit or even a lot?
While the 511 vest can stash a lot of stuff I wouldn't consider it concealment under most conditions. Unless you're in a group of photographers, tourists or are working cameras yourself, not many folks round here wear those any more. IMO, if you want to blend into more areas you're better off with some travel vest or a low key hunting vest like Filson or similar. Even if you have to do some mods yourself to add a push for rifle mags.