Depends why I'm bugging out.
I have a newer import sedan that gets 40mpg on the interstate;
...an older import sedan that gets 35mpg on the interstate;
...a domestic 4x4 that gets 12mpg.
The 4x4 can handle general obstacles better than the cars, but it won't get very far. The only time I can see myself using it is if we get hit with a blizzard and I need to go out before the the plows can do their thing. When we get bad winter storms, I try to go our for a joy ride before the plows are out. I enjoy being pretty much the only vehicle out when everything is covered in a white blanket. You rarely get a chance to see a populated area like that.