I was checking out Dinan's website, specifically the performance software for the 5 series, and noticed the disclaimer: This product is legal in California only for racing vehicles which may never be used upon a highway. Yet my dealer tells me they've downloaded the software on a lot of cars and that it's perfectly legal. What are the implications of this? Will the software make your car fail the smog test? I like the idea of having a BMW with enhanced performance but not at the expense of a hefty fine and a car that just looks good on your driveway.