We wanted a harness for our large dog Ro Ro who gets very anxious in the car...he has gotten worse as he has aged. He is a big boy, so we wanted something snug but comfortable. He gets seat belted in the car and without the harness, he can still lung forward to the front seats when the road surface changes... Very dangerous for all. The harness allows him to move, sit and lay down, but not reach us in the front.
He handled the harness well, even though he had never worn one before. We left it on during a car drive to the vet and used his regular collar for the leash. He appeared comfortable and he looks cute with his red fur and his sea-glass/orange harness :)