The drivers I use for my E-Mu 0204 DAC are exactly the same in Win 8 as they were in Win 8. I know because I have to go through a ton of crap to load them.
That being said, I notice absolutely no difference in sound quality of 8 over 7.
In fact, as I use the USB DAC mentioned above, I noticed I actually have to connect it directly to my laptop, otherwise it will skip and flutter like crazy when using my USB docking station. Never had this problem in Win 7.
I actually like the faster boot time and wake from sleep on Win 8, so I'm staying here. Since the upgrade only cost me $40, I wouldn't feel too bad if I did decide to revert to 7 though.