Hi guys.. I agree this is a great cat but it is definitely not CEL free. Sound is definitely as good, close to full catless.
I have gotten CEL in multiple occasions.. First was driving on the highway normally no WOT, just long trips, 50-200 miles. It usually comes on towards the 150-200 mile mark. Second time i had my JB4 off completely at the drag way, and first launch half way down the straight the CEL came on.