In searching for the next flow collection system that will support your organization, most results will turn up solutions claiming to support the consumption of millions of flows/second. For the most part, I think there is some truth to these claims but, when the system is trialed, the limitations become obvious. 

It’s one thing to collect high volume NetFlow and quite another to report on it and that’s really where the rub lies.  The amount of engineering necessary to collect millions of flows per second and write them to some type of backend really isn’t all that hard for a seasoned developer.