another data point: '02, 1000+ mi on the Berk teepee. no CEL. stop n go city traffic + idling + high way miles. this is on 93oct IL gas + 10w30 Mobil1 (not that these things would actually affect CEL light trip, but just FWIW...)

extremely satisfied with the product.

 

i reset my ecu 3 times and after those 3 times i drove normally and they came back after 50-60 or so miles....the 4th time i reset the ecu and drove it spiritedly and i haven't seen the cel yet (knock on wood) and its been a few hundred miles already.