^^ Agree. When we're talking exhausts though it's also worth noting I think the R&D that major manufacturers have put into the systems. I'm not knocking custom exhaust's either as I used to have one on my old Civic Type R made by Longlife exhausts which was very good but, ...if I ever had taken the car on a dyno I'm sure I would have seen better results with some of the higher end exhaust systems and as Tarmac states the re-sale price (should I had chosen to sell it) would have been a lot higher. If you just want something that's going to make a nice sound you like wmr1980 then by all means go for a custom exhaust which may or may not see good gains but if you want an exhaust that is going to give you a good increase in bhp/torque figures then I'd look more at some of Tarmacs quality exhausts with dyno proven gains.