I am planning to deploy a NetFlow server (using NfSen/NfDump) for harvesting data from Cisco devices;

Are there standard calculations or guidelines I can use to calculate my server requirements, specifically I need to plan for storage. Is there a way of knowing how much data I will collect per day for example, given N flows?

Lets say one device has 10k flows per day, this is typically XYZ MBs, so I can scale this up?

If not, how many flows are you guys and girls recording per day, and how much data is this generating? Hopefully we can generate an estimate from everyone else's figures!

P.S. If it makes a difference, I'll be collecting from <= 50 devices max (non more than 50Mbps each).