Is anyone using a holder to attach an iPad to the front of the car? if so which version is it, a suction glass mount or one that clips to the air vents. I'm trying to decide which one to go for. In the past I've used the glass suction mount type to attach a small PDA to the windscreen which seemed solid enough but I'm wondering if this type is good enough considering the weight of an iPad. Just wondered if anyone had a recommendation of either device.