I’ve been using Solid Edge. Siemens offers a free community edition that works great if you want to create models for 3d printing. I originally used FreeCAD, and while it works, had problems with models breaking when trying to make changes. Solid Edge is much more professional, easy to use, with pretty much all the features available that you could want. The only drawback for me is that it only runs on Windows. Tried going back to FreeCAD since it has the new 1.0 release and will run on Linux, but it felt too awkward. Now I have a dual boot system with Windows solely to run CAD software.