I learned CAD using Vectorworks, learned it largely without help, and still use it exclusively. I just started it up and kept going. It is a designer's program because both object and vector based, thus capable of excellent presentations without ever leaving the program. It can import jpegs and other file types directly. It is self-contained, and includes high-powered 3D rendering. I've never tested its BIM capabilities, but it has a feature similar to xrefs. It has differing modes for layer character that allow color and pattern overlays somewhat independent of layering, although the layer order can be important to the result. It has a semi-layer feature called "classes" which can be schemed to place lines or objects in any layer, including line weight assignments. Still, I use classes very little. Layers can have layer colors just as in AutoCad, but I never use it because layer management is easy without it. As others have mentioned, it makes or interprets good AutoCad conversions for working with consultants. It is ususally good practice to convert only vector files without the objects (solid polygons) used in presentation work, however.
Oh, yes. The price is right. Also, like AutoDesk, Nemetschek (mfr.) runs educational seminars in several cities around the country, and the documentation is quite good. I've attached a small rendering done a couple of years ago.
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Gary Collins AIA
Principal
Gary R. Collins, AIA
Jacksonville OR
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