SelfCAD offers Free Trial, but ZBrush does not.
SelfCAD is designed for Individuals, Large Enterprises, Medium Business and Small Business.
ZBrush is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Pricing for SelfCAD Starts at $11.99/Month when Billed Yearly whereas for ZBrush Starts at $39.95/Month.
Some top alternatives to SelfCAD includes 3D Slash, Clara.io, SketchUp, 3ds Max, ZBrush, formZ, Onshape, BricsCAD and Autodesk Design Review.
Some top alternatives to ZBrush includes Mari, 3D Slash, Strata Sculpt 3D, 3ds Max, Maya, Wings 3D, Modo, formZ and Adobe Substance 3D Painter.