Nice solution! It works like a charm, too.
There is only one technical drawback... the VHD cannot be attached to the host OS with the VM running. In order to even start the VM, the VHD must be detached from the host OS; and in order to access files locally, the VM must be shut down, and the VHD re-attached to the host OS.
I think I can overcome this limitation through some handy dandy scripting to automatically attach/detach the VHD from the host whenever the VM boots up/shuts down, but it's still kind of annoying.