i had 2 of the cvx's in my very last install in my car. with 2 cvx 15's, one kx2500.1, one optima g31 yellow top, and 7.9 cube enclosure, i was scoring 151 and some change while testing for bass race. burp score was 153.3 at 43hz on termlab.
if you swing it overhand it hits pretty hard J/K, in a subwoofer box joe mama is doing 150's thats pretty impressive for the price of sub, install install install, same subs and amp installed at circuit city in a prefab box barely breaking low 140's I bet.