It sure is! We actually fixed quite a few Windows 8 issues for 4.3, so it should be pretty stable! The only major issue at the moment is that windows that are not on the native Windows taskbar don't show up in alt-tab, but we've included an experimental alt-tab replacement (enable it in the Advanced Settings) to work around the issue. It's still got some minor kinks to work out, but if you get a chance to try it, please let us know how it goes.

Thanks!