Michael,

the problem with Blender is that yes I can sculpt and or edit an imported STL for example but to get a nice and smooth model the mesh as to be quite dense and unfortunatly even with an 8 core cpu and 6 gig off memory Blender become quite sluggish, basically unsusable.

Also, yes retopo would be necessary to do something useful with Blender. Fortunatly for me, programs that translate the mesh to something else, either voxels and or bitmap are not as fussy about the mesh structure and size.

Though I can understand the major difference between Sub-D and Nurbs I would have thought the transition between the 2 would have been made much easier by now. Unfortunatly for me, my goal is to machine the model I would create. The mesh needs to be dense enough to be machined smoothly, especially the small parts. I understand also the quality of machined model is dependent on the CAM software and the macine itself.

Thanks,
Felix