I've got some real world experience with this very setup, well, a slight variation. My brother was playing a gig with a Marshall 4x10 combo thing, didn't have enough juice (only a 3 piece, so bass needed to be authoritative), I suggested he DI'd into two of those Behringer cabs you linked to. Plenty of volume, but very undefined (may have been the amp rather than the cabs), so maybe with the right preamp, and a pair of them, it might be ok, although you won't have any serious bottom end. You'll need a sub for that business. Or a 4x10.