no ive got an E90 320D and it only beeps faster and then a constant beeeeeeeeeeeeeeeeep sound if you are in the max range before you need to panel beat or polish!!
But no, it's only the beep, but if you have the NAV, there is a retofit rear view camera that you connect to the screen for a view. But you still have to rely on the beep...
With Satnav on E90 3 all u get 2 c is digaram of the car and colour coding as u approach the object - a little better than the beeping stuff but no where near as nice as the view of a camera