well I am going to try and find a used car with a traditional engine, 3 MPG more may be important to some government agency, however the cost of $400 to clean the engine largely negates any gas savings to the consumer. Just figuring drive 80,000 miles with 32 MPG at $5000 for gas at $2.00 per gallon or drive same with 29 MPG $5.520...its almost a wash if it costs $400 to clean your valves.
