I’d like to share my recent experience regarding Nurbs and Blender.
I made small toy car and prepared Nurbs data for plastic molds almost entirely in Blender.
Its possible thanks to already mentioned Addon “Export to IGS”, it works quite flawlessly.
We already have tools for draft angle and thickness diagnostic (“Mesh analysis”), its trivial to than export it as IGES.
What is missing though is possibility to boolean objects as Nurbs surfaces, not with current boolean modifier (than export to igs obviously doesnt work), this is only step which I had to do in other software.
But even now with this addon its a game changer - no need to buy/learn CAD to make organic shapes for plastic molding!