BricsCAD

Modeling in rendered mode is made easy. You can learn it in just about an hour thanks to the Quad interface, reducing clicks to an minimum.

I use version 17 of the BricsCAD for Linux for aproximately 1.5 years. The review is based on this experience.
PRO:

1. Similar to AutoCAD: 2D/3D dwg files, system variables, supports AutoCAD commands, works well with AutoLISP.
2. Cheaper than an AutoCAD.
3. Has versions not only for Windows.
   CONS:
4. Very unstable under Linux: crashes, freezes.
5. After the number of parts in the model over 5-10 work is very slowed down.
6. Problems with non-ASCII encodings.
7. Very inflexible. Not enough settings, some settings that are not working.
8. Terrible support. For more than a year, I have been contacting the support service and have not received any real help.

[Edited by umix, October 17]