Newer done it with Virtual Server (like to stay away from MS product until at least one SP, or two, has been released). However I have done quite a few things in VmWare.... and since they are releasing their midrange product (GSX) as freeware I think that is the way to go.
This link
http://forum.mikrotik.com/viewtopic.php ... highlight= talks about a testbed I did to check on policy based routing, 6 MT routers in one hardware, and that hardware was also running my PBX, backup AD controller as well as a SQL server at the same time.
/Jörgen