Both are must-haves for Bay fans, but...
Out of those two, COPIUM's better--like someone else said, Keak really grew as a rapper, not to mention that he carried most of the CD himself (something that he didn't do as much on SNEAKACYDAL or HI-TEK, alhthough those CDs were cool, too). As much as I like it, DISOBAYISH is basically just more of the same Messy from before that we know (which is cool as far as consistency, don't get me wrong), but while I like both, COPIUM has the edge. Just my view, though.
PEACE!