I've been running w8 for a year and w8.1 for a few weeks (32bit version)
with no problems on a desktop. (There's a lot of nonsense in the press
about the metro changes but to be honest it is very easy to set it up so
that you work in the desktop the majority of the time.)
The only significant legacy application problem I have come across is with
a serial to usb interface cable that connects an Oudie to the pc for use
with Condor. W8.1 introduced changes that mean the cable chip isn't
supported any more so I have had to change it to a Bluetooth connection.
SeeYou, Spine etc all work fine.
I'd say that W8 has been the most stable release of windows I have used.
Regards Peter