my guess is bobby's going to leave the vsm's alone at their bam-based rolloff (@30hz) and the subs would get it below there.
if you're looking for more stage, bobby's subs will work perfect. if you're looking for impact, i dont know if his subs will do it (after all, the 6.5" is still doing all mid-low bass, and as good as it is, its still 6.5"). but time will tell--bobby is amazing.
that being said, i can say in advance i will keep my entecs.
rhyno