I use several programs that don't exist in iOS format (or even Mac, for that matter) so the Surface Book (same as Pro but with hard keyboard, basically) is my main computer. I work with embroidery digitizing, and most programs only exist in Windows format, especially my preferred ones. I also like that the Surface, being a real laptop, has a mouse. Of all features I'd like to see iPad Pro get would be the ability to use a mouse, probably above anything else, with a real file system being the 2nd one.