Jumping for Joy

My family and friends travel more frequently than most so it's always a treat to have the entire clan together under one roof. I love to find interesting toys and gadgets for savvy niece so I think we can have lots of fun with the kids (available for children too) with these bouncing around on the street. These might be easier on the knees when running/jogging on hard pavement. I am just wondering if I will fall flat on my face. Has anyone try them before? Price starts around $110.

Description: (via areyougame.com)
.....adjust the boot's length to fit your feet, strapping it on right over your athletic shoes. Then start bouncing in place, our bounding across the yard! The high-traction tread is safe to use on any surface - indoors or outdoors, and they won't mar floors. Heavy-duty interchangeable rubber T-Springs transform downward energy into bouncing motions that are gentle on joints and bones.....