The Scorpion would be a good option for stepping up from the OEM system, the Blueflame is louder...
Milltek is closest to OEM with a much nicer sound to it...
Welcome to the forum, the Milltek system we do would fit the bill for an OEM replacement or if you wanted some more volume then I'd opt for the Cobra Sport system we do, feel free to drop us a call, email or PM and we'll be happy to help...