Yep, the polys and edges on the gen 3 meshes were set up very nicely for detailed musculature and realistic bodily deformation.  Rigging them, however, was a pain because of the density of the verts in certain areas, but I successfully rigged V3 years ago in 3dsmax with a Biped rig, and it deformed well.  Not perfect, but that's my own shortcomings.

Genesis 1 and 2 can be very good for both deformation and rigging, in the right hands, because they subdivide the best of any I've seen up to this point.  So with the subD, you'll get excellent morphing results, and rig at the lower poly resolution, like in high end applications.

The facial polygon distribution on the Gen 3 figure in particular was not very good.  The mouth and expressions were hard to get looking realisitc.  V4 was a little better, but not much.  Miki 1 had excellent edge distribution around the mouth and nose, which made her facial expressions a pleasure to work with.

---

Tools :  3dsmax 2015, Daz Studio 4.6, PoserPro 2012, Blender v2.74

System: Pentium QuadCore i7, under Win 8, GeForce GTX 780 / 2GB GPU.