I can honestly say I have never driven my BMWs with the windows open. Partly because BMWs - even the fun M-cars - dont really have the sound I absolutely love.
My other car is a Maserati GTS so I put my money where my mouth is.
You have got to try it before you diss it, that active module is surprisingly good that most will never even know its there. Perfect sync with engine and throttle response.