From my limited knowledge of both packages, I can shed some light on generalizations...
FormZ - Great 3D modelling tool. To use with AC you will need to export/import the geometry between softwares.
MaxonForm - Specialized version of Cinema 4D (see below) made to work with AC through the MaxonForm plug-in. Letting you work seamlessly (to a point) between the two softwares.
Cinema 4D - Great 3D modelling/rendering/animation tool.
As with any software package, each software has their pros and cons. In the end it is up to user preference.
David Larrew, AIA, GDLA, GSRC
Architectural Technology Specialist
a r c h i S O L U T I O N S
WIN7-10/ OSX 10.15.7
AC 5.1-25 USA