Windows 8 to Windows 8.1, laptop would regularly take 10-15 minutes to restart or shutdown, the fingerprint reader locked me on the login screen in a way that I couldn't even login using my password so had to restart with the power button, the hard disk and processor usage when the system was idle would suddenly jump to 90%+ for extended periods of time (especially problematic if on battery), WiDi dropped dead and several other 'improvements'.
After restarting the laptop for a gazillion times (which took 10 to 15 minutes each), I managed to update all the drivers but sadly WiDi and the fingerprint reader were still not working and the disk and processor usage would still jump to around 90%+ if the system was left idle for around a minute so I've had to switch off any form of background maintenance tasks the OS might perform.
I must admin though, despite thousands of posts in forums, HP and MS support staff are still extremely polite and paste the same solution in response to pretty much every problem: "run teh virus scanner and if there are any viruses, remove them", if no viruses are found and the person seeking support is persistent enough: "Update teh drivers", updated drivers: "... ... ... [crickets]", so much better than the OPs experience