He should ask for the O2 extenders. They basically pull the O2 sensors out of the flow of exhaust a little more. Many have said they work most of the time. You may through a code but it'll clear later.
Let me get this straight... You are swapping out parts designed by some of the top engineers in the world because some guys sponsored by a company told you it's "better??" But when you ask the same guy about tracking, "oh no, I have a kid now" or "I just detailed my car." or "i just got new tires."