Anyone using freeCAD?

I am a newb to 3d printing and modeling.

I've tried tinkercad and I like it because it's incredibly simple.  Though in just a few uses I already run into some of its limitations.

Autodesk 123D is cool, it just has so many quirks that I get annoyed and throw up my hands.

I've not tried 3dtin, but I hear it is also nice.

I'm not necessarily looking for simple, so much as something I can stick with and put the effort to learning it.  I realize this is a very broad subject and it's going to take me years to get really good at it.

I'm looking at freeCAD it seems pretty solid, but I'm seeking advice in this area.

If you could start fresh what software for modeling would you pick up and stick with??  Money is a concern since this is just a hobby and my wife would kill me if she found out I spend nearly 1K on a printer and another 4k on modeling software.

Reason I decided to get into this was mostly to satisfy the hardware spectrum of my robotics hobby.  So mechanical design is going to be important part of the software though initially simple gears that I can download from thingiverse will suffice.

thanks