I think you are missing the point. This is not for someone looking for max hp. This is for guys (like me) who can bolt one of these on and get a little extra performance for not much cash. Sure I could buy a h89 head (for up to $800 if you believe the ads on here), spend a bit getting it machined, buy a VRS kit and bolt it on, get an old weber and a adaptor plate, get the weber overhauled because it has been sitting on the shelf for 5 years then get the whole lot tuned.
I bought one because I want a little extra poke and I dont want to spend the earth. Mine would be lucky if it has ever been past 4500rpm let alone 6000. Im not looking for something I can bolt on and take on hsv's at the lights, just let me keep up with a camry and make the grin a little bigger on a sunday morning through the twisty bits.
Yep, there are better options out there, absolutely, and there is no doubt this is not the ideal solution for all, however it is what it is and that suits me fine. I dont want big hp at big rpm.
Lastly, CFM is cubic feet per minute, cubic feet is what you want to measure.