I agree a vm is a good idea for some senarios, but the one in software center
does not allow usb conectivity. It is better (imo) to get the puel version on
the virtualbox website if full functionality is desired. Another thing to think
about is what sort of OS you want to test. Testing unity or gnome 3 in a VM is
not practical since 3D composting is required and support for that in a VM is
poor at best.