Nitronome is more versatile than BAB. To compensate for a slight increase in damage and a lot more knockback, the BAB is penalized in blast radius, walk speed and fuse time. This makes the BAB difficult to use since it cannot be chained easily like the Nitronome. It does have nice graphics/sounds though.

If you were to alternate Shiver with BAB that might work ok. That isn't a typical bombing pattern though, it might not be very efficient since you are only doing damage every other drop. Usually you'd alternate Shiver with Levi Charge where the Levi's damage would compensate for having to drop the Shiver. Or just chain Nitros, letting the mobs come back into the blast each time.

Here is a video of Rits doing some Shiver/CIV action in an arena.
Here's Eeks showing a Nitro chain to kill off Greavers.

Finally, Eeks wrote a long post on ways the BAB isn't able to function well in any bombing role:
http://forums.spiralknights.com/en/node/9924?page=1#comment-78983