Subdivision Surface would probably be the better choice. NURBS and SDS have the same smooth surfaces, but NURBS is much more difficult to handle. But I do not know if Pixel3D's Tempest renderer is able do work with these, since their own software seems not to use them.

A ship in port is safe; but that is not what ships are built for.
Sail out to sea and do new things.
-"Amazing Grace" Hopper

Avatar image of me done by Chidori.