I only walk Lilo on a collar. She is trained to walk correctly and doesn't pull or jerk. I've never been in a position of having to pull her up off the ground so I don't really think or worry about that very much.
She rides in a crate in the car so no car harness either. I guess part of my thoughts is that I really really disagree with harnesses for training and larger dogs so I just never think about them as an option.