I came across this RadiANT DICOM Viewer tutorial that in just eight minutes gives you quite a good overview how to use this viewer, including rendering 3D, reconstructing multiplanar views, using measurement tools and much more.
I’d dare to say that for a typical user, the RadiANT Viewer is vastly superior and easier to use than Slicer 3D.
The only real drawback that it is a paid tool, however, it gives a trial for 30 days which later can be extended again and again, just with each extension there will be a longer “delay” before it can be used, and eventually the sessions will be limited to 15 minutes. For a “typical patient” it’s more than enough, and that is fair price to pay for one who doesn’t want to buy the license (which isn’t very expensive too, by the way, about 40 USD (60 CAD) /year).