This video from Color Cartel shows the traditional Wacom Cintiq tablet setup and use vs that of the iPad Pro.
At about 3:48 into the video, you get a sense of all the setup work you need to do to get started with the Wacom Cintiq. The idea that you have to hold the stylus in one hand and the mouse in the other seems incredibly clunky and inconvenient.
Watch the video, see for yourself.