Our experience with the 2006 Highlander Hybrid (4 wheel drive) is that it is great in most conditions. On our steep, paved driveway, I got stuck in the snow bank (passanger front tire in deep snow). I could not get power to the wheels to pull me out (took the shovel and cleared around the front tire and than no problem). WHEN THE VEHICLE WAS STUCK, I COULD NOT GET ANY RESPONSE OUT OF THE ENGINE TO REV UP. I suspect the reason was: The rear traction motor does not have enough torque when the front tires are not moving and that the front gas engine won't torque up if the rear motor dosn't torque - Make sense??? Anyway... we love the vehicle (and will carry a shovel).