Wow, seems like this guy tried to spout a bunch of BS on you. Nice to know.
Just installed the Air Straightener for the Mazdaspeed CAI this past weekend which was easy and took a total of 5 minutes. I did not have any CEL issues before the straightener but the car does run richer with the CAI as opposed to the stock intake. I have however noticed that the car does not Surge randomly at WOT like it used to before the Air Straightener, hope this helps.