Secondly, a car with a turbo, from the factory or not, will not benefit from an aftermarket intake, because airflow and temperature are dictated by the turbo, and not the air intake itself. A forced induction car doesn't have to draw air into the itself, rather it's forced in, negating the 'improved flow' of an intake, and the 'cold air' aspect of an intake is also defeated, because whether the air going in is 25 degrees or 90, it wont be after it goes through a 200 degree turbo impellar, and the very act of compressing air raises it's temperature.
If you wanted to improve your air intake system, i'd get a k&n drop-in filter for your factory airbox, and if you're buying in to the 'colder air' hype, grab a bigger intercooler, or invest in water/alcohol injection, because that's the only way to achieve colder, more dense air into your turbocharged car.