I've tried the plugin for SolidWorks. The huge advantage in my opinion is that you don't have to create curves & sections to generate a nurbs surface. You can manipulate points, edges or faces on a surface right from the start to get the shape you want, its much more direct I think, and can save quite a bit of time for more organic stuff.

I never had a chance to play with edge weighting (my demo expired), but it seems like it could be very useful for objects where you want a combination of hard and soft surfaces with smooth transitions (blends) between them.