I've owned both and the iPad Pro was better for me in almost every way. The main issue with the Surface Pro is the horrid windows software eco-system, especially around touch interfaces. Almost without exception windows touch apps are terribly designed.

This is what I am hoping for. I want to have my tablet mode with iOS apps and interface. Then I want to switch into laptop/desktop mode, being able to spin up any desktop application.

Even more a dream state: would want a docking station that allows me to use my multi monitor setup.