Sigma,The CP-E intake comes with what amounts to an air-fuel tuner as well. This adjusts your A/F ratio for optimum power gains throughout the powerband. The difference is quite staggering compared to other CAIs.
This link here provides some details on it, however these are for the "tunable" version which most people don't get. The regular version doesn't give you access to these things to change them, it just provides you with the base optimized map whichis fine for 99% of applications: http://www.therpmstore.com/product_info.php?products_id=246
It also doesn't throw Check Engine Light as other CAIs are prone to do on the 3.0L.
Having run the "regular" CAI (an Injen) and the CP-E, I can tell you that the difference is stagering. And that's coming from an Injen which already was significantly better than the AEM and loads better than the crappy K&N.