Zbrush is THE PROG for Movie, game industry or Illustration from volume!
It's the standard in 3D for refine or create an organic volume as Autocad is the standard for CAD!
(Modo has a great speedy render inside, Silo is low cost modeler but after you export to Zbrush ;)

He can manage billions of polygons in real time
It import any organic format OBJ DXF file (low or medium poly) for refine it with extreme accuracy!
it can't make animation (except turnable)
it can paint on 3D volume
It can work in 2D, 2.5, and 3D (Drawing, painting, sculpting)
It make a Map hight Quality for put it on model low poly for animation for other prog!
It's the best prog for Sculptors artist! (out the other technology of "voxels" who is born with 3D Coat 3 month ago:)
Sensation of sculpting garanted with a graphic tablet!
Take a look on the gallery ;) You can't see the same anywhere!
http://www.zbrushcentral.com/zbc/featured2col.php