Just to chime in with another data point, the BRB that my younger brother raised from a baby bit him all of 3 times over its entire lifetime, 2 of which occurred when it was still very small and defensive, and he attributed the third to an error on his part, so I'd say they're not necessarily any more nippy or aggressive than any other snake. As others have said, as long as you don't overheat them (mid 80s at the warm end of their enclosure is really the max temperature) and provide them with a big water bowl, you should be in pretty good shape. Obviously you may have to adjust based on your local climate (if you're somewhere super dry, you might have to mist in order to maintain humidity), but they're really not difficult to care for so much as just different than more commonly kept snakes. Meet their requirements and they'll thrive.