I am hearing a lot of these ECU chips that are supposed to increase my car's power by injecting more fuel into the engine. What are the pros and cons of using this chip> will i be consuming more fuel per mile??? any long term issues?

There are complete ECU developed and manufactured by Python Fuel Injection in Calif
this ECU hooks up with simple hand tools and is said to increase HP by 25% thay also produce racing Fuel Injectors and air flow meters the AFM is adjustable in the cockpit to run your car rich or lean