Those devices, do indeed, work.
For testing purposes, make sure that Windows or NFS file sharing is enabled.
Make sure that there is at least one visible share, preferrably public.
If it is not finding the device, you can try checking the Advanced > Configuration > Unknown Devices page, in the web admin for your NAS.
You can also check the SambaScanner.log and NFSScanner.log files in /var/log/pluto to see if the system is seeing your device.