How do you intend to use the model?

If it's for a rendered image, modeling in polys will give you better results for less effort/time.

If you need the model to actually make a physical part, there are reasons for choosing to model in polys or nurbs

3D printing and CNC routers can use polys to make parts in plastic or wood.

If the need is to make a steel mold (ie. for injection molding, some types of casting, or stamping) or a steel part, then you will need a nurbs model. Although milling machines that cut steel can use polys, the poly model is almost universally rejected for this.