Has anyone tried both devices doing business level tasks?
I've got the following toys:
2016 12.9" iPad Pro
Surface Pro 5
13" Surface Book 2 w/1050 GPU
Why two Surfaces? I'm a developer, and I originally had a Dell XPS 15 laptop but when it died it was still under extended warranty from the MS Store, and they replaced it with a Surface Book 2.
So, what do I recommend as a daily driver for "business" tasks? It depends on what your business tasks involve. If you need to run Windows-specific software than the iPad probably won't cut it. But if you're talking Excel, Word, Powerpoint - you can definitely get by nicely with the iPad although proper mouse support would be nice. I find most other tasks (like web browsing) much more pleasant on the iPad than either of my Surfaces. You are still going to get a *better* MS Office experience under Windows 10 though, for obvious reasons.
Despite their respective specifications, I find both the Surfaces to be laggy when compared to the iPad, especially when scrolling large pages of content.
I don't enjoy managing Windows on the best of days, and especially not on a tablet (too much like my day job). Last November, my Surface Book 2 began to randomly blue screen after boot-up. I spent a week trying to figure out the cause when it turned out that Microsoft had started pushing out "testing" updates to anyone that clicked on "Check for updates" in Windows Update - even if you weren't part of their insider program. iOS has had some good bugs over the years, but I've never had to waste a week on it.
That said, file management is (currently) much better on Windows than iOS - so if you're juggling a lot of files around between different applications you might find it easier to do on Windows. But iPadOS is going to help there, and honestly, I'd rather deal with some file management hiccups on iOS than the hassles I go through with Windows 10. So much so that I'm putting both of my Surface devices up for sale later this week, and trading the 2017 iPad Pro for an updated model.