The only time I've had mine up in the air was to change the oil. When I saw the whole side go up, I put a stand under the rear jack point - figured that if the jack let go, the stand would hold the whole thing up. I haven't had the need to poke around much under the car, but I know my roadster has some frame-stiffening braces - I would think that the ends nearest the outside of the car should be solid enough for stands.