If you look at the fine print, you can get it for free. I have a year right now. I mostly work on a Mac also and keep my Windows box for T-Splines & Grasshopper.
I am not sure I want the learning curve right now, I am way more comfortable using T-Splines, which I purchased late in the V2 cycle, giving me a free (or really cheap, I don’t remember) upgrade to V3 and a nice discount on Autodesk T-Splines V4.
I don’t know FormZ at all and if I had the time I would probably learn Fusion360.
FWIW «Randy