Bests & Worsts Reviews from Amazon

I ordered 16 of these for classes at our gym. Only 4(!) classes later (that means not even 4 hours of use!) and all 16 have rips in them. The handle bars shake and rattle, no matter how tight you screw them in. Rarely was someone heavier than 175 lbs on them. Most of the women using them for that short period were anywhere from 115-150 lbs. Not only are they tearing--- they have folded up and collapsed on three people! I called it the human venus fly trap. Not safe at all. Returning all 16 for safety reasons. I've attached pictures of only three examples.