well its either a chip or a flasher, the flasher isnt much more than a chip at all and is well worth the extra money cause with the chip you have 1 fuel setting, yes you should be running high octain anyways but with the flasher you can get, low,mid and high octain prograhms. and all you have to do to switch them is be on almost an empty take grab the xcalibrator and load the new setting up into the obd diagnostic port and 20-40 seconds later you are golden
