Interesting... the one fitted on my current car is great. Mid range acceleration is much improved and fuel economy... well I do an average of 57mpg. Need I say more.
As for the noise, you could hear a sort of breathing noise when it was first fitted, but now 20,000miles later, there is no noise whatsoever, and hasnt been any since about 500miles after fitting. Maybe cos I had it fitted by an approved dealer/fitter.
Does anyone have any good experiences of one fitted on a Cup?