If you’re a typical Windows user, by now you’ve likely found a pop-up window from Microsoft on your desktop at least once inviting you to “reserve” your free copy of Windows 10 – even if your current system is pirated. It’s an unprecedented annoyance step for the software giant to take – what, are they going to run out of copies soon? Or is every previous OS so flawed that they must be replaced ASAP?

Neither, apparently. Microsoft says that while Windows 7 mainstream support ended on January 13, technical support won’t end until 2020, and Windows 8 won’t end until 2023 – just 2 years before that for 10. Which means if you’re happy with the version you’re using now, you shouldn’t need to change at all for quite a while. In fact, if you have an older computer, you might not be able to upgrade – here’s how you can check.

Granted, Windows 10 offers a slew of new features (though most can be added to older systems without installing a new system) and has garnered many enthusiastic reviews. It’s got the tablet-style touchscreen features from 8 and has brought back the much-missed Start Menu from 7 and before. It has a phone assistant, Cortana; Edge, a new built-in web browser to replace the constantly-targeted and patched Internet Explorer; an Apps Store; users can log in with face or iris recognition; it works with smartphones; help is more easily available; and the interface, search functions, and screen organization are all said to be generally improved.

Yet like every new operating system, Windows 10 still also has a number of bugs. But that’s not the reason so many are leery of upgrading. One might be that even if you don’t want it, you might be stuck with it anyway. The installation files (around 6 GB of them) could be automatically downloaded onto your machine even though not requested if you use 7 or 8.1, have reserved a copy, and have automatic updates enabled.

Not only that, the files dump into a hidden folder, named “$Windows.~BT” just to make them more difficult to remove. And once Windows 10 is actually installed, however, it can be very difficult to remove and go back to an older system.

This sort of “helpful” high-handedness, however, is only a symptom of why one should be cautious. Windows 10 could break your favorite applications and also does completely away with the Windows Media Center. And according to some interpretations of the End Users Legal Agreement, it may be able to scan your system and block pirated games and “unauthorized peripherals” – though whether it actually will or not is still debatable.

But the chief objection is that Windows 10 is essentially spyware with its constant, invisible, and invasive data collection. This is nothing new: Microsoft has long been accused of sneakily harvesting user data, and recent updates to Windows 7 and 8 have raised concerns about the amount and purpose of the data they suck up.

Windows 10, though, carries this to a whole new level. By default, 10 sends back everything you say to Cortana, all your Bing queries, and even if you carefully go through all 13 screens to disable sharing, it will still send data back to Redmond.

But there’s more: Windows 10 can steal your bandwidth to help others download the software, and share your wireless password with others. While all this can be helpful, and can be disabled, the mere existence of these “features” shows a disturbing trend.

The basic model the computing world relies on, that sharing data “pays” for services and software, is more and more becoming involuntary and removed from the control of individual users. And there is no oversight, no limits, on just what these giant, faceless corporations are using it all for.