Having owned my CR-V for about 6 weeks (and very pleased with it still), the most I have done to it is add a set of mudflaps, front and back, and a protector for the cargo step (have dog, will scratch!). The rear roof spoiler seems an attractive addition, but I am wondering if it adds anything more than a little bit of cosmetic 'flash'. Does it, for example, improve rear tyre adhesion to any perceptible degree? Or just keep the rear window from getting too muddy? Or nothing at all? I'd be interested in anyone's views. Since I do not trust myself to do the fitting (yes, I have seen the web how-to videos), it would be some expense at the dealer's. Is it worth the money? Thanks in anticipation.