I am going the HFC and Y pipe combo with stock exhaust. I dont want my car to be loud, but I want the performace. This setup has been used by other members with good results. In my opinion spending around 2k for a exhaust setup for 25 whp is out of this world. My combo CNT HFC 375 + OBX Y pipe 200 = 575. A little more sound and performance (maybe the 25 whp)