For balance, here's an 'everything is good' point of view
http://www.zdnet.com/article/no-microsoft-is-not-spying-on-you-with-windows-10/
From the article:
"Any company that offers modern computing services has nearly identical language in its privacy agreement", true, but before w10 MS was mostly 'the good guys' regarding personal data gathering, now they join the pack (of wolves ;O) full time (and forced to do so, as an attempt to compete with google and apple).
"We expect personalized services. We expect relevant search results. We expect the devices we use daily to get smarter and more useful over time. We expect them to understand us despite our accents when we use speech-enabled features"
Up to anyone to accept transfer of personal data (due to perceived usefullness), or choose some actions to minimize privacy impact.
As for the OS itself, I've found the latest 10 release stable and reliable on the tested laptops, but nothing fantastic or special, certainly no practical reason here (speed, stability, function etc) to kill off any current 7 or 8 license to get 10.
There's a bunch of telemetry-stopping programs apearing, like this >
http://www.oo-software.com/en/shutup10. IMO some good program like that + not using MS for everything (search, email, cloud, msphone etc) may make 10 eatable in the long term, as it stands now got zero rush to replace any 7 or 8.1 installs.
