Hello mate, I hope I can help you with my example. I have my laptop With Win7, Backtrack 5 and Ubuntu 11.10. On Win7 partition i have installed VMWare, in VMWare i have 4 VMs: Win7 (to play around without mess with my documents), BackTrack 5 R1, CentOS and Windows XP. I also have my old computer with Windows Vista and Windows XP on dualboot.
Technically its the same. Since I share the hosts IP on my VMs, this is like the host works as a Router and the VMs are in a new network. This configuration is made by VMWare you don't need to bother with that.
For example I have my incorporated Wireless antenna and a USB Wireless Antenna. Sometimes with VMWare i connect one my USB Antenna to BT5 VirtualMachine and the incorporated Antenna on the "Victim Machine". And play around with wireless attacks and somethings like that.
My point is, by using any of those methods I don't have any problem, so perhaps you should choose the method that suits you the most. Both work really good.