As the IT manager for my team's school, I believe I can shed some light on this topic. Of the two choices mentioned, I would recommend using the Surface Pro, as it runs the full Windows desktop OS (I believe the current model runs Windows 10 Pro). The Surface Pro should be able to run the full-featured EV3 development environment, just like if you were using a Windows desktop or laptop.
Hope this helps :-)
Daniel Woodfin
Lead Coach
Team #24104 ("Riptides")
Warwick River Christian School