Rdietz,I stopped by AFE today and talked to Nick,They do have the flow numbers for the Proguard filter. I have the excell spread sheet with all the numbers. It will be added to Mr Bobs website soon. But for now I can tell you that it flows 698 cfm @ 1. 5"h2o.
This should answer your question and put the guesses to bed. I personally have never seen any of those outlandish claims. I have seen their flowbench,dyno,shop,and have learned a lot from my visits with Nick. I will try to figure out how to post the chart here.
Bob