I'm going to get the C&L CAI and Tuner kit from Brenspeed. I have an 06 GT 5-speed that is a daily driver and I have plans for some occasional weekend autocross. I also have the Flowmaster catbacks. I was wondering if there is a big difference between the aluminum street kit and the plastic Racer Kit. Any durability problems with the racer kit? I like the look of the Racer a little better but I want to get the best one for my car. Any help would be appreciated.