So I finally had the ability to lay hands-on a coworkers SP4 extensively and my conclusion is that all this fuss about dedicated tablet UIs and full Windows lacking in tablet mode is somewhat bogus.
As I learned Windows 10 has this feature of scaling all elements a bit bigger, which makes operating even full blown Windows with your finger a complete non issue. I didn't even have problems dragging and resizing application windows to my liking. All without the pen!
If you think about how tiny some input elements in your smartphone browser can become physically (on webpages), it's a nobrainer. Everything worked like a charm. Of course you're going to need some sharp fingertips in places, but really, at this day and age I think we're all long accustomed to how accurately operate even tiny elements on touch screens.
The only two things Microsoft hasn't nailed yet from my PoV are the keyboard (a bit unsturdy/plasticy) and battery life (4 hrs according to my colleague). But anything other than that, I was basically blown away. Nobody in his right mind would even think about using an iPad again when an SP4 is laying on his/her desk.
What's your take on it? How hard or easy to finger operate is full blown Windows on your Surfaces?