I've found it's easy to mistakenly think it's fully latched when it isn't. I applied 3-in-1 Lock Dry Lube to the mechanism, and now it's easy to fully seat it. I've also missed one of the three attachment points a couple of times but caught the error before rolling out. They're only rated to 80 MPH (~130 km/h), but I've had them over that without losing one (yet). Now I'm wondering if I should just ratchet-strap them to be sure. lol