I've used the military version of the HAWG for about 3 years now (though not military). I like it a lot. The main compartment is on the smallish side of "just right" for me, but I can live with it.

The front "pocket" is great, & has smaller pockets & sleeves inside, including one with an elastic strap (such as to secure a walkie-talkie). As someone else noted, using other containers (Pelican boxes, decon kit containers, stuff sacks, etc), along with the pockets, provides quite a bit of organization.

Additionally, the compression straps on the sides are of sufficient length to permit things to be secured under them (blanket, jacket, tripod, machete, whatever). I added a couple of side pockets from REI, designed to go on the compression straps of almost any backpack & provide additional space. I keep them handy, but not attached to the pack, unless I need them. Even when attached, the straps can still be used to secure large items, too.

The MOLLE/PALS attachment points all down the back face, & a couple more on the bottom, are quite useful, too.

The only real complaint is that the body of the pack is too short for my torso, so I can't use the "waist belt". However, the strap management system is great, & keeps it out of my way. I've adapted some of their ideas to other packs.

Just my 2 cents.

David