I think I did: lack of reactivity between the time you click on something and something actually occurs on screen (talking about OS feel in general), same applications running much slower on Windows, higher general memory consumption, extreme sluggishness when running multiple applications in parallel, extensive usage of scratch disks while OpenSuse seems to be able to use RAM more effectively...

I find it hard to believe something else isn't going on because some of those things are the exact opposite of my experience. Firefox has always been more responsive on Windows. Its acceleration architecture is still more advanced on Windows. In fact, everything is more responsive and opens faster on Windows. The scheduler is way better for desktop use. Windows never becomes unresponsive for me because of background applications even though I have the scheduler set to prioritise background processes, whereas even quite recently on Linux I have still found compiling or such in the background can lead to X temporarily becoming unresponsive. Windows is certainly leagues more stable than KDE (if that's what you're using). In fact no part of Windows has crashed for me in years.

These are just my experiences. I have other problems with Linux on the desktop too mainly relating to GPU stuff. Personally, while I love many aspects of Linux on the desktop and use my Linux VM all the time, I would say I still find the overall experience to be "just deplorable"

It's strange that we have both very much opposite experiences. I'm not sure what you are using when you mention "linux" because responsiveness depends a lot on the distro. I wouldn't use Ubuntu, for example. As for Firefox, I guess it depends on your config/RAM/processor, but i have a i5 with 4 gigs of RAM and opening Firefox with saved tabs is slow as hell on Windows 7 while much faster on OpenSuse. By the way I'm using KDE and I don't think it's that bad in terms of stability, while I have experienced a few crashes (maybe once a month or something). It's true that Windows (from 7) has become very stable, nothing like what XP used to be: it does not crash to blue screens anymore, but it still can become very sluggish when I do audio/video editing and basically nothing much runs in parallel because it's just unusable.

It is strange. I've used gentoo for years, arch, debian, ubuntu and probably others variously. All pretty similar experiences though I agree on ubuntu.

I don't know, maybe it is only my experience, but I have tried Ubuntu quite a few times over the last years, on three different machines, and every single time I experienced problems, especially GPU related, speed is always an issue as well. Just try to search for something in Ubuntu and it just doesn't feel responsive. I'm in no way saying that windows is a better platform, but if you have enough RAM, it is a fast OS.

I'd say it's Ubuntu, based on my experience trying many different distros.

I eventually found that turning off Aero and 90% of the stuff in Performance -> Visual Effects made a huge difference on my Core i7 laptop with external monitor. (Windows 7).

The giveaway was high memory usage by "dwm.exe"; it seemed to have enough memory pressure that unused windows would have their decor paged out, so switching between applications had to wait for a page fault to be serviced from disk.

Sounds like something is wrong with your computer or you have really old hardware.

Maybe take a youtube video that shows this?

all of these points were significantly more of a problem in windows XP, especially responsiveness under ram pressure and 100% cpu load.

Windows 7/8 has made all of these issues significantly better. If you are comparing XP to modern linux, its not much of a fair comparison to compare a 13+ year old OS to a modern one.

My favorite one is being unable to delete an open file - this has consequences on upgrading software that has to stop running and release its files before the upgrade starts. There are also the various ways Windows Explorer fails with very long paths. Or the subtly different ways the CMD.EXE fails on the same use case.