Personally I also ran into some inexcusable bugs on my first try of FreeCAD recently. Sadly I don't have the link anymore, but the problem was offsets being inc

Personally I also ran into some inexcusable bugs on my first try of FreeCAD recently. Sadly I don't have the link anymore, but the problem was offsets being incorrectly calculated in certain cases, and I found it to be a long standing bug in their issue tracker. There wasn't an easy way to work around it so I had to look elsewhere. Too bad, because FreeCAD did seem quite fine otherwise (Note: I never used SolidWorks, and my demands are amateur level). For programmers I highly recommend OpenSCAD or Cadquery, which let you write code to build your models instead of using GUI. With this approach, "parametric" comes naturally, and so you don't need to learn a special constraint system, it's just your code (and a bit of math). Cadquery was a bit hard to get started with being essentially a bunch of python scripts, but it's also more versatile and more powerful than OpenSCAD, and has a good collection of examples in their docs. OpenSCAD is still great for e.g. building simple models for 3D printing.