Can't say I'm a fan and I looked up a proper one to compare the differences of which their appear to be quite a lot, including the price.
Never quite got the whole 'make a car look like a super car' thing, it just seems to me that you want to impress poor people and those without a clue. I fall into the poor people category but needless to say it's never impressive.
It's like having the worlds biggest d!ck, which is brilliant.. Until people find out it's not the real deal.