While the sports exhaust is nice to have as an option since the car is used and you won't be paying extra for it. All it does is allow you to switch in "loud" mode for a throatier sound. It gives you no power gains at all. If I was changing my exhaust I would go aftermarket in order to get great sound and increased power for the same or lower price compared with the factory option. 
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2006 Lamborghini Gallardo 6spd-Rosso Leto
2006 Range Rover Sport Supercharged-Winter Beater
2006 BMW 750i 19" Sport Wheels BK/BK-Daily
2005 Lotus Elise Sport & Touring Package-Fun
2001 Lexus RX300-Back-up Winter Beater
2001 Mercedes-Benz S500 Sport AMG-Sold
2000 Boxster S Heavily Modified-Sold
2000 Nissan Altima GLE-Parking Spot Holder
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