I have a 1999 Primera Sport+ 2.0 VT6 Auto, this car, although it has leather headrests and is pretty much top of the range (apart from the SE+) the headrests are non adjustable backwards or forwards, although they go up and down. Head rests are not for comfort, they are correctly known as head restraints and are a safety feature, not a comfort feature. Most 70's cars and older did not as a rule have head restraints, they were only added from the late 70's onwards as car makers had to become more safety conscious, and were required to add safety features such as head restraints, rear seat belts, crumple zones, side impact bars etc. They are only there in case of an accident to prevent whiplash injuries to your neck, that is why they are adjustable for height. I do agree though that other makes do allow forward and backward adjustment, but it is not necessary and I have never used a head restraint for resting my head on whilst driving - if you are that tired to need to do this, then you really should not be driving, but rather getting some rest.