I think the most important thing with keeping them (not that I do - but I plan to) is knowing what your options are if a bite ever occurs. Death Adders, tiapans and the like, are "exotic" species when it comes to states such as Victoria, yet are readily availible for purchase. "IF" a bite should occur, your choices of seeking "effective" medical assistance can be compromised serverely, as not every hospital in Victoria has the need to stock these specific anti-venoms.
I believe that even though you'll get some weird looks from hospital staff in relation to this, I think it's imperitive that you notify your nearest hospital about the certain "exotic" species you plan to keep and whether they have the ability to handle a situation should it ever arise. JMO - safety first, as always.