Well, I did the update on my win8 laptop today. I should have listened to my little voice that said not to do it a week before I'm gonna take it on vacation.
Nothing "wrong" per se, but some stuff is slower. Firefox takes three times as long to start as it used to, but the edge browser starts immediately (like Firefox used to). I also had to remove Classic Shell because it would hang when I tried to open it (gonna try and reinstall it later). Libre Office started just about as fast as before, so on the browser, I can't help but wonder if MS is doing some kind of "Why isn't edge starting as the browser?" check that slows down Firefox.
Also, Lenovo has a message that pops up for a few seconds every time you switch to a different screen mode (laptop, tent, tablet). It used to just flash, but now MS has captured the messages somehow and they show up and collect in an MS 'notifications' window, which is a bunch of extra clutter that I don't need.
Maybe it will just take a little while for everything to recognize everything else. Or else I'll be spending time I don't wan to spend going through and tweaking crap. I'm definitely not upgrading my Win7 machine. Maybe ever.