Hi, i am planning on buying an exhaust for my Coupe soon and i wanted to know which one is better in sound and performance .. i am leaning towards the greddy but then the Injen kind of looks better so i am having a hard time choosing an exhaust which exhaust would you guys choose .. and is there any numbers out for the greddy exhaust ?? cause i've seen the stock dyno with the exhaust at conceptzperformance.com and it says it got like 15rwhp or something like that .. please help me out guys thanks .