With about 1,500 stores, O'Reilly is one of the nation's largest specialty retailers of automotive after-market parts. Much of the appeal of this 50-year-old firm is that demand for car parts and accessories is relatively stable, since most automotive work is done out of necessity rather than by choice. That provides the stock with some downside protection even in a slowing economy. O'Reilly's $2.2 billion in annual sales is split evenly between do-it-yourselfers and professional installers, giving it a broad foundation. And Morgan Stanley analyst Armando Lopez says O'Reilly has terrific growth opportunities, figuring the company can triple its store base from the current level. Reinhart calculates the firm's PMV is $40 a share.