I just bought a 2012 LTZ RS Turbo. I'm wanting to change the air intake system. Should I purchase Injen or K&N. I've noiticed from a lot of pictures on here and videos on YouTube that most ppl have Injen. But I would like an honest opinion of which brand is better and why ( price vs quality)? I'm also looking at changing the exhaust so which one should i modify first? Thanks!