Also, If you drink a lot of energy drinks, you may want to look into getting a Sodastream machine. It will more than pay for itself in the $$ saved by making your own energy drink vs buying the Rockstar & Red Bull energy drinks. My nephews all love the sodastream energy drink. I'm not a fan of the energy drinks, but the other soda flavors are pretty good. I'm still using the sodastream i got for christmas. If nothing else, the sodastream is fun to use when company, and small children are over..