Best car speakers...?

Look into Elemental Designs e9.65i. They are 6.5" component speakers (can also be mounted like a coaxial speaker). Although they are $225 a set, but are directly compared to speakers on the $500 - $800 range. Other than that look into the new Prime line from Rockford Fosgate, they do sound great and get plenty loud. Speakers on the outside of the vehicle is not legal and the police will confie your system.