The tuner actual re-programs the computer for higher octane fuel, and leans the a/f ratio, etc. Those other "chips" do little to nothing. Some modify the voltage on a sensor to lie to the computer to modify a/f ratio, but don't really produce results.
The only thing that actually works is a hand held computer that re-programs the computer. DiabloSport is the leading manufacture, but their are others.
07 3.5L Charger K&N CAI, Magnaflow Cat back, JBA shorty's, DiabloSport 93 tune sold, 2010 Challenger R/T 5 speed. 180 degree Thermostat with fan settings lowered, CC, ceramic brake pads, slotted rotors, red and black caliper paint, Challenger label for calipers, Corsa Cat back, functional hood ducts, and hood struts, 93 DiabloSport tune, JBA Shorties, and Mopar drop in filter.