Although I use Crobat and Toxic like, all the time, I still prefer other types. For you poisoning lovers, you had better watch out for Zangooses and other poisons.

I LOOOOVE TOXIC! My Tentacruel knows it and its really useful! Just use that, Giga Drain when necassary.... Ooohh Yahhh

Poison types are alright, but a good water type with toxic makes a much better team member than a purely poison one, poison types don't have enough move variety when compared to a lot of other types...if the attack variety is improved it would be great.