As an automotive designer with 20 years Siemens I-Deas, Catia V5 and Wildfire experience.....Alibre Design has all the functionality that a hobbyist or small business requires. The free download allows small assemblys. The drawings update when the associated models are revised. Translators are included (at least in the purchased version) STEP, IGES, ACIS, stl, DXF, DWG. It is very intuitive.....if you are familiar with wildfire you will be up and running in no time......Also the greatest user support forum and with purchased. If you require free-form surfaces....it works great with Rhino as well.
HTH!
Denis Kansier