Why would you run Snow Leopard in Fusion 3? You either can run Fusion or you cannot. If you cannot then even in emulation it makes no sense, does it? Also this would circumvent Apple's ROM in the code ... maybe down the road it would be supported on newer OS X 10.7.xx or higher but natively in Snow Leopard or lower just doesn't make sense.
Why would you run Snow Leopard in Fusion 3? You either can run Fusion or you cannot. If you cannot then even in emulation it makes no sense, does it? Also this would circumvent Apple's ROM in the code ... maybe down the road it would be supported on newer OS X 10.7.xx or higher but natively in Snow Leopard or lower just doesn't make sense.
If all you want is a "sandbox" to play around in, wouldn't a better approach be to simply clone your system to an external drive and then boot from that?