It really depends on what sort of work you are trying to do. If you are an infrequent user and you want to do some very basic 2D conceptual sketches or drawings, then you should give the AutoCAD Freestyle Technology Preview a try. It is intended for entry-level users and has a very limited feature set.
If you need a full featured professional level CAD application complete with 2D and 3D functionality, a command line, full customization, etc, etc then AutoCAD is probably best for you. We have free trial versions of both so that you can decide for yourself.
Lisa
Lisa Crounse
Product Manager, AutoCAD Freestyle Technology Preview
Lisa Crounse
Sr. Product Manager