For anyone that's worried about losing their warranty. As long as the part you installed doesn't have anything to do with what ever part would need warranty repair or replacement the dealership is legally binded to honor your warranty. So for example you install a new exhaust and there's a problem with the ignition system, they're still supposed to cover the warranty. Even if its actually related to the problem they still have to prove that the part you installed is related to what caused the problem.
I will be modifying mine with some minor exterior touches. Why? Well, Infiniti did really well with the body lines and I'm just finishing it off the way I would've liked it and should become an option.