KS5 will be able to do both, you have the choice. When a NURBs model/assembly is imported it will use the default mesher and tessellation engine it has always used, but you have the option to import NURBs data too, then when the model has been imported you have an option to switch to pure NURBs mode, a bit like Rhino does at present with it's render-mesh.

Martin Spencer-Ford