What are the main differences for 3D Modeling between versions of Bricscad?
Bricscad V12 Classic has no 3D modeling features but ACIS Solid viewing enabled.
Bricscad V12 Pro has Full ACIS modeling and editing, Direct Modeling, Rendering and Section Planes features. Also Modeling in rendered mode is made easy.
Bricscad V12 Platinum offers Pro enabled features plus 3D constraints to the model and Design intent option to keep full control on the model. X-Solids and X-Hardware libraries included.
And note, Trial version of Bricscad has all 3D capabilities of Platinum version.