For some years I had a BH Tactical EOD vest. Now it is a BH Modular vest. We tried to carry the whole equipment with the vest, but it is uncomfortable. I removed all the webbing on the back side to save weight. I prefer to combine it with a backpack.
In the Modular vest: knife, goggles, compass, mosquito head net, med pack, gloves, fire starter, spoon, light, whistle, Camelbak and a snack; There is a Nylon cover for the knife etc., so you dont see any of the equipment (and the cover is civilian green).
I like the vest because of the Camelbak (I put it into the top lid of my backpack while walking, or in front of my belly if the backpack is too heavy). And I personally hate jackets or smocks with many pockets. Imho carrying a vest is much more comfortable.
Second reason: one of the pockets makes a great arm-rest for long distance walking.