Personally, I find it very useful - especially in multi-story car parks. In addition, twice I've avoided squishing a local cat who seems to like sitting under the back of my car (can't think why on these cold days!) I'm of the opinion that bumpers should not be used to judge when to stop!

On the 991 it also has a graphical display front and rear rather than just beeping. 


--

991 (on it's way!) XC90 - Black/Black 2 kids, 1 dog