I luv the really really low bass that 18's reproduce. My friend has a pair of Kicker Solobaric 18's that he had in his car and I liked they way they sounded. the box was actually quite small fo the subs, like 2 cubes per sub and it sounded great. Low bass extention like no other. I'm not looking to have the loudest bass setup but I do want to enhance what the BOSE system has and add what it lacks.. LOW BASS response. I already replaced the radio with a Pioneer CD/MP3 reciveer and the difference i ridiculous. Just wondered if anyone on the board ever tried them in an E.....