Thanks. I agree it would not be as effective as with harnesses, but certainly better than nothing if I'm in a car without harnesses. I guess the next step is to find one at a track event and sit in the car to see if I'm comfortable with the seating position.I have used the carbon fiber R3 for 2 years and like it. The only thing is that the R3 backbone and pad push you forward in your seat, so that the seat sides are not securing the driver as well. if one gets into an accident with the R3 without a harness, I suppose it is better than nothing, but the shoulder harness do go over and push the backbone wings down. Without the push down, there will be more head movement.