Is anyone aware of any official recommendation against using a Hatch mounted bike / bicycle rack ? The rack itself says do not attach to plastic, but I believe the hatch on our 2K7 Mazda5 is fiberglass? And I'm open for opinions from all on this. I did "fit" the 3bike Bell rack to the car, but never drove it or even put a bike on it, I was more interested in whether it would fit.