Every Windows 8.X update I've used has made improvements to it.
Windows 8.1 was a pain in the arse to apply though but once fully running it was excellent.
Windows 8.1.1 is an excellent update. I do look forward to the next update based on past results.

I upgraded to 8[.1.1] during a HD upgrade. Have had no issues at all...well I still can't seem to grok what the whole Metro thing is about but I'm not complaining.  Win 8 ++.
 
Regards, 

I just upgraded to 8.1 and lost the ability to collectively control my Pro channel modules. I can quick group all my channel fine for other purposes. But... if I want to turn up the drive, for example, on all of the console emulators at the same time and by the same amount, I no longer can.
 
It's not that big of a deal and I expect minor stuff like this when upgrading. I am curious if anyone else has run in to this yet?

Ha I just ran SFC /SCANNOW for fun.
The results were not fun on multiple Windows 8.1.1 installations upgraded from Windows 8.0 :(

So much for tiptoeing through the tulips.

I started with 8.1 and Sonar X3e and have been pleased with the flow of projects....once I figured out how to fire up the Garritan VSTs. :)

Another happy camper here with 8.1. Great improvement over 7. But I did one update about 4 or 5 days ago, an intel graphics update, which has made a major improvement. I dont run a graphics card, just straight off the MBO, twin screens. I run a pretty beefy system with an SSD for windows and programs, as most do here, and start up time for X3 was usually around 5 secs, with project load times, usually around the 20 second mark or so. I was pretty happy with that. But now, with this latest update, it's a blink of an eye to load X3, then around 5 secs for a project. I'm stunned at the improvement. I really do like win 8 too. Very much a step forward for me.