We have just installed the JIC Bullet Spartan SUS505 Exhaust and HKS front pipe on a MY03 WRX. This vehicle already had a 3" exhaust, which we replaced with the JIC system and HKS turbo front pipe.

Below is the Power run results which shows torque improvement with a 10hp increase over the previous 3" exhaust system. This system also meets JASMA standards and keeps the noise decibels (Db) within legal requirements, while giving a throaty boxer note. Will post up pic of exhaust sytem fitted on vehicle shortly.