Having used a Surface Pro 3 as a daily work machine for a year, I'm so pleased now to be back with an iPad Pro 9.7 **and** MacBook pro 13". Windows 10 when used as a laptop operating system is fantastic (on the right hardware), however it's an abomination when you use as a tablet O/S. As for the hardware, my Surface Pro would turn itself off at times, not wake up 40% of the time from sleep, have problems recognising the pen and worst of all the fan noise was often so annoying that I'd use my 2011 MacBook Air for some tasks.
Other odd things were the poor way Windows supports scaling where the primary 4k monitor is paired with a 1080 external monitor, it just looked shocking with odd dialogue boxes and odd font sizing everywhere & the Keyboard Case would stop working a few times a day.
The bit that got me most annoyed was the act of opening it, instead of just lifting a lid, you need to open the keyboard case, raise the bottom of they keyboard case to "raise it" then open the kick stand and then you are ready to go, assuming the bloody thing would wake from sleep without a hard power cycle. As a fairly mobile worker, this was actually quite annoying compared to a MacBook (or other laptop). The other thing is that I found the Surface Pro to be impossible to use on my lap or any un-even surface.
But I still think that Microsoft are on-to something, they gave it a red hot go and should be commended for going in their own direction on this.
Looking at my iPad Pro and MacBook, I kinda like the two devices, gives me a very flexible mobile office with multi screen (either native apps or with AirDisplay 3) and provides me with heaps of working options as I roam about.
Dam I love finding better ways to use technology in my life, at least here I'm surrounded by folks who feel the same and don't judge.