There is a big problem with the Replay XD 1080. Just like the Contour line, it can only be mounted on a bike helmet. While GoPro charges $40 for their Chest Mount Strap, it is still worth the cost. Because, Instead of the camera being mounted on the helmet, where anything could happen to the camera by a cyclist not watching where they are moving their head. With the Chest Mount Strap, not only will that, not disrupt with aerodynamics. It will also keep the camera from getting easily damaged, when the cyclist moves their head.