So if I had any reason to doubt Manga Studio before, it took about 5 minutes of having it installed at work that we ran upon this sweet little feature.
There are POSEABLE 3D MODELS in there!!! I actually started from a static model ( but I had the choice of a variety of nice poses ) and articulated everything up to each finger joint.
Since it's in a drawing program already, I just alpha'ed out the layer, made a new one, and sketched away.
And importing them is super easy too. Put all the model files in a zip file, then drag and drop on the stage. Yup. That easy.
Manga Studio retail for around 70 but is usually on sale for like 50.