Well just to give you an example, if you do production work for an automotive company its likely they won’t accept a model with dozens of XNurbs surfaces. They would reject you model but they would may also pay you the licence costs for Icem or Alias.
Toolmakers People dealing with the constructive parts, for example, do a lot of offsetting. If you get a heavy surface from XNurbs or surfaces with local discontinuity, this would fail more often, meaning they need to redo alot of your work. So time you save is time they do more because of “your lousy work” and nobody wins.
Garbage in, Garbage out
See this thread for x nurbs examples: XNurbs Rhino plugin is available!
The problem is basically its “variational” nature They fit and smooth in a surface unless its tolerances are okay. If its not possible it increases span count, but if you actually measure deviation on the edges (something Rhino 7 can do now ) you would measure local discontinuities, which do increase if you offset for example…
Really its hard to tell for anyones purpose. Maybe you ask XNurbs for a test version and check if it works for you.