maybe I'm missing somehting, but I don't understadn the question.
when I see VM, it means Virtual Machine, or I guess on these forums Virgin Media
a NAS would already have an OS on it, which you would probably access via a web page from one of your PCs to confgure etc, browse the files, kind of liek you do for a router.
I don't think you remote desktop to them.
not sure where you using a VM? people use VMs on physical PCs to access different OSs etc on one PC.
edit:
just googled it, this it?
http://www.ebuyer.com/666187-qnap-ts...FUg8GwodCSAB5Q
I think you can use it as a server with a hypervisor so you could install different OSs on it, and remote connect to them, or you could just use it as a NAS.
the hypervisor OS is just a means to install an OS, you can't usually do anything with them, it's to get your VMS as "close to the metal" as possible without the overhead of a fullyu blown OS just to host VMs.