i've had a lot of cars all having intakes
94 toyota celica - injen intake - NO CEL
98 honda prelude - AEM CAI - NO CEL
99 honda prelude - fmax turbo - custom chopped aem intake - NO CEL
98 integra GSR - Ebay intake - NO CEL
00 Jeep Cherokee - PVC Pipe and cone filter - NO CEL
04 Nissan Sentra - Ebay intake - NO CEL
04 Mazda 6 v6 - Ebay Intake - NO CEL (AWESOME SOUND)
All in all... I really dont know how the all the different brands work with the mazdas, but I have the ebay and a friend has the Injen on his. Neither of us have check engine lights, but mine actually has better sound than his. So make of it what you will.