If you’re a Windows 7 or 8 user who has been determinedly ignoring all the nags and tricks Microsoft has been employing to try to get you to upgrade to Windows 10, you’re about to have a big decision to make. Tomorrow, July 29, is the last day you can take advantage of Microsoft’s offer to upgrade your computer to Windows 10 for free.

According to The Verge, after that it will cost $119 to upgrade your computer to Windows 10—commensurate with the $93 (for an OEM package) or $130 (for a white box version) you’d pay for it new on Amazon. But Microsoft’s still willing to give it to you free through tomorrow.

Is it worth the upgrade? Bearing in mind that some people may have specific reasons for wanting to stay on Windows 7 or 8, I think it is. Windows 10 has been out for a whole year now, which means it’s had plenty of users, plenty of bug reports, and plenty of opportunities for Microsoft coders to smash the bugs—and a comprehensive “Anniversary Update” patch release is just a few days away. This isn’t exactly an untested OS. By now, it’s pretty darned stable. I’ve been using it for the last year, and while it had its shares of glitches that necessitated a couple of reinstallations from scratch early on, I’m pretty happy with it by now.

Although I never had the chance to use Windows 8.1 for very long, I’m given to understand that Windows 10 is a significant improvement over that version. It includes a lot of the Windows 7-like features people complained that 8 was missing, and it has been fully compatible with any Windows 7 desktop application and Windows 8 store application I’ve tried—including the 5.1-surround capable Netflix application. Windows 10 includes access to the new app store that includes e-readers like Freda, too. While I don’t think Windows 10 is necessarily a great tablet operating system, it’ll still be better than Windows 8. So, if you have an upgradable Windows 8.1 tablet, you might as well do it while you can.

Of course, it will have a new interface and some new odd foibles to learn. (My favorite is that pressing the Windows key alone will get you a search/run box with entirely different functionality than the one you get when you press Windows + R. I still mix the two up every now and then.) But then, any new operating system will. Wouldn’t it be better to get it now for free, rather than wait until you absolutely have to and then pay for it?

And the longer time goes on, the less good it is to run an outdated operating system. Microsoft’s mainstream support for Windows 7 (that is, extension and improvement beyond basic security patches) ended in January of last year, and it will stop patching it altogether in 2020. Windows 10 is still good through October, 2020, with extended support all the way out to 2025.

The final decision is yours, and I’ll grant that you may have good reasons for staying put where you are that I would have no way of knowing about. But if you’ve just been putting it off for no real reason, or because you’ve been annoyed by Microsoft’s ham-handed attempts to force the upgrade on you while acknowledging that you’ll have to switch sooner or later—well, waiting any longer will cost you $119 when you finally do get around to it. So if there’s any conceivable reason that you might want to upgrade to Windows 10 in the future, you should seriously consider going ahead and doing it now. Yes, it might be a little annoying. But how much more annoying would it be to know you could have done it for free?