One MechDesigner USP is how it solves the kinematics. We use closed-form solutions that are very fast and robust. Most CAD packages do not solve the kinematics in this way. Typically, they will use a 'solver' that minimizes error. These are not fast and not very robust and often fail at certain configurations. We challenge all other commercial kinematic, mechanism, linkage, motion, cam design software to be faster at solving the kinematics.