At 8BitDo, “Ultimate” does not automatically mean “better” than “Pro”. The main difference between the two series is their shape and the arrangement of the D-pad and analog sticks.
Pro series: Inspired by classic SNES and PlayStation controllers. The D-pad sits at the upper left, with the left analog stick below it. The two analog sticks are symmetrically positioned. This layout appeals to fans of classic controllers and players who often use the D-pad.
Ultimate series: Inspired by modern Xbox and Nintendo Switch Pro controllers. Here the positions are reversed: the left analog stick is at the upper left, with the D-pad below it. The analog sticks are offset.
Important: The series name does not tell you which controller has more features or better technology. Connectivity, supported platforms, stick technology, triggers and extra features vary by model. Choose based on your preferred layout and the individual controller's specifications.