Up to you really. On a question like this you'll find there's a bit of an echo chamber for people who have decided they don't like Windows 8 and if you reduce all of their complaints down, they all amount to how they don't like the new start screen. You do get a few Linux users griping about Secure Boot, legitimately to be fair since Secure Boot is about 90% security theater, though they tend to misdirect their complaints at Microsoft rather than the UEFI vendors and major OEMs who push it.
Personally, I find that there are a number of very nice improvements in Windows 8 over Windows 7.
* The revamped task manager, which folds in a lot of the functionality of the old msconfig tool on top of a almost complete visual overhaul to make it easier to pick out information, is a very welcome change IMO.
* Same as the native ability to pause/resume file transfers, which is something I've been wanting since the Windows 2000 days. So that gets two enthusiastic thumbs up from me.
* MS did a lot of work to try and reduce the boot time in Windows 8, which is always nice.
* More of Aero is done in the GPU than CPU, which is also nice.
* Windows 8 has been put on a pretty significant diet to try and make it so tablet makers can cram it onto even lower end hardware, but it benefits everyone.
* The right click menu on the start button has been a real time saver for me, letting me quickly get to specific areas of the control panel with only two clicks.
* There have also been a number of under the hood improvements, continuing the work MS started with Vista, refining a lot of the real low level components to work better with more modern hardware. There are a number of subtle, but very important, differences between multi-CPU systems and single-CPU multi-core systems. XP was built before multi-core CPUs existed, so treated each core like discreet CPUs, creating a number of inefficiencies. Vista ripped all of that code out and replaced it with code that can tell the difference between discreet CPUs and multi-core systems. Windows 7 refined that as the number of cores grew and now Windows 8 refines it even further.
* Windows 8 has the ability to natively mount ISO files. I personally rarely need that function, so it seemed like I'd install some program for that purpose, then several months would go by and I'd uninstall the program, then a couple of weeks after I uninstall it, I'd need it again. Now I can just say screw it, and use Windows 8's built-in feature as-needed.
I still prefer the "glass" look to Windows 7, but I have come to appreciate the savings in screen real-estate that comes from Windows 8's more minimalist look. Especially on lower resolution laptop and tablet screens, every pixel counts.
To people who can look past the surface and beyond the start screen/metro interface, Windows 8 has a number of nice-to-have improvements for desktop users. Whether or not those are enough to justify the cost of Windows 8 will depend on each individual. There are a number of nice-to-have features, but nothing I'd call a must-have if you're using Windows 7. If you were using Vista and wanted to install a SSD, the TRIM support alone would probably be worth the price of admission.
I know this question has been asked a lot.
But I want fresh answers from people who have used win8.1 extensively over the last few months.
So is it worth switching from win7 to win8.1 for advanced and heavy desktop use?

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