I got my last few from GSF, after getting one from the dealers and it being faulty I had a massive argument with the dealers because they said in order to test the MAF you need to take your car to them for them to test if the MAF is faulty, what it DOESNT say is if you are running a modified engine in anyway it voids the warranty, as the warranty is the ONLY reason for buying one from the dealers, if your modified just get one from GSF or ECP simples