I went from a "guy-and-his-dog" type camp setup with an Xterra and rooftop tent to "guy, wife, infant, and three dogs." Something had to change, because none of that was going to be feasible. I got a Thule roof box and a ground tent for a while, but ended up selling the Xterra. I'm now in the market for an Oz tent RV3, which is unfortunately too long for my Thule Force L box. I'm trading it in for a Thule Alpine box - long and skinny - so I can put the Oz tent inside the box and call it a day. Much more secure that way.
Long story short - roof boxes are super convenient, even for overlanding. I'm planning on traveling with my little Subaru and big roof box in the spring, getting 30MPG and a very comfortable ride, and reaching our destination with everything we need up top. Should be perfect for all our camp gear.