personally im completely against 6x9s /ubbthreads/images/graemlins/smile.gif
they will attract thieves if not properly stealthed
they drag the sound stage too far back, sound should come from the front /ubbthreads/images/graemlins/laugh.gif
and if you have a sub in the boot you will get bass cancellation, as well as possibly damaged 6x9s if your sub moves a lot of air
apologies for preaching /ubbthreads/images/graemlins/smile.gif
but back to the question at hand, as Andy says fit a sub and amp, results will be much better and the stage will remain in the front /ubbthreads/images/graemlins/smile.gif