Well I lost my original reply, because I dont know what Im doing.
But what I had said, is that my instructor is teaching us to run two or three tools. atleast nessus and nmap. And to my understanding it is due to the banner captures in some tools arent always correct.
I was also told that an Admin can change a banner to say version 3, when in reality they are running version 2.8. They could make that change to save them the trouble of being caught by the board for not running an official update or upgrade on their insecure apps.
Just my 2 cents, but I am interested in seeing what other people are doing.