I trust my dealer, lets face it the "customer" added a bunch of crap to his car,like ebay chips that require,according to the poster, new bigger fuel injectors.what a waste of money and bad judgement to boot.i think you stated the cai and ecu chip were maxing out the fuel injectors?but then state he spent the money on non-needed parts?a little confusing to say the least. i think everyone should notice the problems that folks are having with the custom cai's,error lights and poor running,excessivly bad fuel milage.I think the expert engineers at mercedes thought out pretty well the fuel mixture and stock cai airflow for our engines.it seems a lot to sacrafice the reliability and fuel economy of the factory set-up for the miniscuel gains we have seen from these cai mods.