Which surface are you comparing it too, the surface 3 LTE that came out in May? Not sure that is fair to compare it to a product that is unreleased. The reason I can't compare the newly released Surface 4 pro to the ipad pro is that they are completely different animals and the Surface Pro 4 is a full laptop meant to compete with Macbook that doesn't have LTE. But what does the Surface 4 pro have that the Macbook doesn't? touch screen, a freakin USB port, and micro SD. I didn't like the micro USB charging port, Apple's magsafe2 charger was may better, but Apple ditched it in the new macbook!
The surface 3 LTE is heavier then an Ipad Air 2, but has a lot more productivity. I went shopping with someone that needed business productivity where their current Ipad was failing. And they went with the surface 3 LTE which is a shame because a new one is just around the corner. But if you need it and can't wait, then you do what you need to.
The point of all this and all I could think of yesterday was Apple has serious competition now. I still hate windows but man has Microsofts new hardware catch up or surpassed Apple in some areas. And the new surface book is pretty awesome, except I think it broke while I was playing with it. And the microsoft band is a horrible joke. But I can see Apple eventually going down the road of the Surface book, just like the Ipad Pro is similar to the Surface.