[the_paco]

Vectric's Cut 3D is a 3D CAM only... but a heck of an entry level 3D CAM.

MeshCAM Art has very basic features to create 3D relief from bitmap (color assignment). Still, some people can do a lot with only a hammer...

VS3D is more advanced 3D relief creations using several tools and features. Unfortunately, from what I've seen before, it lack a 3D engine to make it more comfortable to model in. Interface is a little awkward to get used too...

Rhino CAM seem capable but, to be honest, I don't know much about it.

ArtCAM is really advance but is way too expensive and lack good support. Make sure you really want it... ArtCAM is a CAD/CAM package as well as Rhino and Rhino CAM puggin, MasterCAM and Virtual Sculptor 3D (VS3D); meaning "you got it all" in a single package... at least it a well used marketing aspect...

I personally prefer to model in CAD; either Sub-D (meashes) or NURBS. Even when I start with a sketch or a bitmap.

I use MeshCAM (known as standard now) and Cut 3D to toolpath my models.