I use a Maxpedition Devil Dog as my small BOB and due to the fact that It's probably loaded more heavily than intended and the fact that I suffer fom no butt, I use an Combat H-Harness (or H-Suspenders) to hold it up. This setup has the bonus of adding attachment points to the back so I can add my ThermoBak, backpack or other pouches to it, as well as the front so I can clip on other items.

Any time I go hiking I take it with me. It gets the odd look or two from other hikers with traditional backpacks or buttpacks with no suspenders.