I think it's mainly down to workflow. FreeCAD forces you to do things in a particular order or you quickly encounter its sharp edges. Some of the nuances are annoyingly subtle, the classic example being bodies created in part vs part design.
Via/Shark feels much more flexible and low stress to me (caveat being that I'm not a pro, I'm just using it to conceptualise/plan out household projects for now). I can quickly rough something out and then add fidelity and details as needed. The downside of that flexibility is that some of the model management features are less automatic, for example you end up doing your own layer management. And the entity tree, while being theoretically quite powerful, isn't as nice to use as FreeCAD's feature tree IMO.
In terms of feature differences, FreeCAD has FEM which is actually pretty decent. It also has raytracing, but ViaCAD gives you quick and easy photo rendering when you need it. ViaCAD also has a few more import/export options, especially once you get to Shark/Shark Pro, but that's probably not important for most hobbyists. A big plus for FreeCAD is its scriptability. Having an always-on Python console is really nice.
Personally I find FreeCAD to be quite intimidating for day to day tasks. I know it can do a lot of things, but I feel like if step off a well-trodden path then my model is going to explode. Admittedly the newer versions are getting better in this regard, and 0.20 looks to be quite promising if the topographical naming fixes make it in.
I have high hopes for FreeCAD (especially now that the Fusion 360 honeymoon is over) but generally find myself reaching for Shark first.
Edited by user Saturday, October 17, 2020 11:26:48 PM(UTC)
| Reason: grammer