If you want a system goes boom during action movies, you need a good subwoofer. With your limited budget, you are better off with maybe buying front 3s and getting a good subwoofer. Get any of the Polks from Neweggs or Frys. Maybe even the Infinity Primus and use your current system as surrounds. And the rest of your money, invest a subwoffer from eD, SVS, or HSU, MFW 15.