Re: New to the GC WK2, looking for an 3.6L Exhaust...
What are you looking to get out of the new exhaust system? Better performance, better milage, cooler exhaust notes? You might want to check around some of the threads that have had different people that have tried this and haven't found significant changes or in some cases it has been bad on their performance, mileage or harder on the engine.
You can always add a molar or K&N cool intake filter and see if that helps. I just have the K&N air filter and don't notice much change, but I like having a second filter on hand.