hey guys im just wondering planning on changing my exhaust sooner or l8ter at the moment i have a 2.5 inch cat back with a ractive muffler which was a wast of money im planning on mabey just changing the muffler to and hks muffler or and injen muffler but i was look at the greddy dt muffler dos any one have one of these systems i would like to know more cuz they sound like the make and sic different cuz i know exhaust systems and there basics and the hole size to power ration some one fill me in on how that muffler can help you gain more power or is this a hole load of **** to sell the exhaust but its only usd$449.99