hi all cost me £340 for cat-back, i do think petrol's sound alot nicer but oh well lol when i first start the car does make a burble noise but only lasts for about 2 secs then it sounds nearly as it did standard and if you rev the exhaust when not driving you cant really hear it atall its only when your driving and you nail it after 2500rpm it kicks in and sounds well nice but when driving slowly its asif it isnt there which i hink is great although some people like the noise constant brmmm lol will try and get a sound recording tonight but it does sound very similar to CupraPIP's