Congrats on your new ride and welcome to the site. You should post some pics of your GXP, is it the street edition? Which CAI (cold air intake) did the owner put on, and this 50hp chip what is it? Never adding that much horse power unless they are talking about the range, which they probably are. As for your exhaust, I recommend going with a custom system (thats what i did), you should run a search for G6 exhaust on you tube and you will get to see and hear all sorts of different systems, if you don't go custom then the GT-R system has made a lot of g6 owners very happy.