ehh honestly I'm not a big fan of the solo X. it's got a relatively short Xax due to it's design. It's got a high rate of coming apart, literally during use, and it's sound quality is about like two cats screwing at high outputs. the two 13W7s will, properly powered, be louder than the solo X due to more combined Xmax and surface area, and similar power with 1Kw to each 13W7. however, the W7s will sound leagues better than the solo X ever could hope to sound.