There are no cons, at least from an artistic standpoint. The reason for having them is to allow vertices to deform more smoothly and more naturally by having them affected by more than one bone, according to the weight associated with it.
It gives you massive improvements to the way the joints deform, particularly with higher poly models. And as videocards get more and more advanced, "low" poly models are getting higher and higher.
It gives you massive improvements to the way the joints deform, particularly with higher poly models. And as videocards get more and more advanced, "low" poly models are getting higher and higher.