User blog comment:Crimson and Darkness/Volume 25 discussion blog/@comment-2405:205:118C:74F6:7DFF:974C:AC29:922E-20180425050623/@comment-28884330-20180425052642

Juggernaut Drive is irrelevant now that Issei has DxD, which is much more powerful. On top of that, the Juggernaut Drive consumes the user's life so it might adversely affect the ambiguous state of Issei's life force.