MTX has really enhanced their stuff to try to compete with the line JL has. They came out with the Thunder 9500, also known as the "sledgehammer", last year to try to compete with JL's W7's. This year they have gotten rid of there regular Thunder 4000, 6000, and 8000 series and replaced them with the 4500, 5500, 7500. and 8500 series. The 7500, 8500, and 9500 are their new line of "superwoofers". They took everything and made it better, such as 3" voice coils and higher power handling. The subs are much larger than the older series as well. The 8500 would now be compaired to the W6v2. The lower models also match up to JL's lower model subwoofers. MTX is making better quality subs now adays, in order to keep up with the competition.