Monster Beverage's (MNST - Get Report)  stock performance should scare investors, as the stock has fallen 20% in the last six months. Monster recently gave upbeat revenue estimates for the year, but TheStreet's Chris Laudani believes those estimates look high and that the energy drink business is slowing faster than expected. While Monster Beverage struck a long term deal with Coca-Cola  (KO - Get Report)  more than a year and a half ago, the transaction hasn't done much for Monster's shareholders. The deal made Coke a preferred distributor in exchange for a stake in the company and some asset exchanges.