After messing around with this form factor for a bit (I have an iPad), I think Android, or some other touch-enabled OS is more suitable for this device - large tappable icons.
If you install Ubuntu on it, you’ll also need to carry around a small Bluetooth keyboard (with that track nipple thing), to make it usable enough.
Windows / Ubuntu has very poor touch-support in my opinion, everything is really too small! I see lots of people buying beautiful Surface Pros, then sticking an old wired mouse into it, or using the built-in trackpad…its funny really…its like someone wanted a tablet really bad, yet they didn’t want to abandon the old input methods.
Regarding my experience with the iPad, I have found that “most of the time”, say 75% of the time, I can use the onscreen keyboard just fine. So just prop-up the screen at an angle, and tap-away. Yes it does take some time getting used to, but once you “master it”, you can type really fast, and its convenient because you don’t have to carry the extra keyboard with you.
Now if I need to do some heavy duty typing, or coding (and my laptop isn’t around), then I take out the Bluetooth keyboard and pair it (pairing is an extra step). Also some apps / websites are not optimised for onscreen keyboard usage, so having an external helps - so again it boils down to “how the UI is built around an onscreen keyboard”.