I tried rephrasing the question title about five times before arriving on this title.
Does nTop have the "built-in facilities" to process sFlow data so that a graph of source and destination of traffic can be revealed/processed in from the .rrd databases?
I have come across some other solutions, specifically nfdump/nfsen, but I can not find a clear answer to my question.
I'm currently opting to use sFlow over a port span/mirror only to see if it makes sense. I will be monitoring several slow links that will all range below 100Mbps.