Like other add-ins there is never a smooth process. Cadmapper works but only gets down to 12' topo increments. I don't mind bringing cad topo into revit, and the process is fairly easy. There is just no direct way to get CAD topo. I also do not want to learn a Civil design program just to get topo for a site that is mostly just for rendering.
It seems like Autodesk should have an easy solution in the AEC collection that does not have me buying an add-in, or learning Civil software I would not use otherwise. I think Revit should be able to download historic topo directly from the "Project Location" dialog.