How to best scan a known host?


I´m trying to figure out what should be the best way to scan a host that I know well, thinking about the time to complete the scan and it´s accuracy. Is it better to run a System Discovery scan first, and then run the desired scan (Full and Fast, for instance), where this scan will be optimzed based on the System Discovery Scan, or is it better to create a new Scan Config selecting just the Families or NVTs that applies to my host?

For instance, if I know I have a Suse Linux host, can I safely exclude AIX, Cisco, and other families from my scan config?

Thanks in advance,