Can't imagine anything negative about either. A Bean Animal is just a Herbie with a separate dry emergency.
If they are executed properly there is not a down side I can think of. They are both dead silent, redundant and simple to tune. If your overflow is drilled for only two drains, run the Herbie. If you have to drill your tank you might as well drill 3 holes and run the BA with that extra level of redundancy.