It runs just fine on Vista.
You might also want to note that quite a lot of people who are slamming Vista will say something along the lines of 'that's why I haven't bought it', which indicates they either don't know what they are talking about cos they haven't actually got a copy of it, or they have a bent copy or an early beta, which is hardly the ultimate benchmark. So in either case, it makes many of such comments invalid. Vista is not perfect, but it's not the disaster many say it is either. I've run stock SH3, GWX SH3 and stock SH4 on Vista, and 1914 Shells of Fury (the XP German release version) and Dangerous Waters too, its runs them all without any problems whatsoever.
Chock