SparkLe works just fine on Windows 8.1. So does the new Sonar and Reason 8. Stock laptop, nothing special.
That's quite an old thread you replied to there, but I would have said "in my experience" before giving SparkLE a green light even now. I'm hoping I will get to the bottom of my problems with it under W8.1, because in my experience it is not working at all well, and the problem is not with Spark2 but the controller, which almost never connects properly, and absolutely never after system boot - I always have to fiddle with settings, sometimes for hours before it either connects or I just give up because the music idea is long gone either way.
I (try) to use Sony Acid Pro 7 and Ableton 9 Lite together with an EMU 2x2 and a Focusrite 2i2 for the MIDI and audio respectively. The reason I use 2 DAWs (not at the same time) is due to having material in Acid that I still need to work on. The laptop is a bog standard Asus X75A (i3).
What I think is happening is that W8.1 is fiddling with the drivers on a regular basis even though I've disabled automatic update/configuration of drivers. Since I have
been able to get it to work, I know it can
work, it is just plain unreliable and the problems may be due to other components, but I ought to be able to use this setup without the connection problems I'm having.
I've not yet raised it with Arturia because I'm hoping I can figure it out, but it has been months now (I have other things to do as well!) with no sign of stability whatsoever. My personal feeling is that Arturia need to (software) engineer a rock-solid link to the controller to head off these problems without relying on MS drivers (I was a software engineer for many years), so my vote would be for a specific driver for the controller interface.
With Windows 10 around the corner, which I believe will need to be left open for updates unless we keep it offline, the chances of something changing in the system without our "permission" might raise the risks of something breaking without user intervention. The randomness of SparkLE in W8.1 (in my experience!) makes me wish I'd bought a 32-bit laptop with W7.
As it is, it is a week or two before I raise this as a support call, because it is getting crazy now.