etunes, as you will read on several threads on the forum, are plentiful. the great thing about them are that they are piggybacks, so that they can be removed when you take it in for service. even with the magnuson act, dealerships can and will void a warranty if they suspect that you have messed with the tune. with an exhaust, some are carb certified, some aren't. with my stinger and the racechip black that i have installed, the dealership and the service department are all on board and have helped in changing the plugs over to the upgraded ones when i blew two plugs at the beginning. they put it down as a fluke on the factory plugs as opposed to writing down that i had a tune installed. but they are all gearheads and do track their own stingers. i know that when i had the problem with the paint, several of the techs that kia sent to oversee my car were interested in what i had done. good luck on your choice, read up and compare the different options available. whatever you do end up choosing, just know that all of one different ones have improved the power, some more than others. it all boils down to what you want and what you will do with the added power. post some pics when you do install them so we can all revel in your joy.