Logitech MX610 left handed using SetPoint with Uberoptions. Both of these worked without a hitch on my old machine (XP64, Quadro FX3700). No special dual screen software - just what the Catalyst driver settings allow. I’m not using Hydravision.
Generally, I’d say that my impression of W7 + dual screens + Firepro V7800 vs. XP64 + dual screens + FX3700 is that it’s a substantial backward step. W7s’ handling of dual screens leaves much to be desired. I can’t even stretch the taskbar to full width.