We use ours on every outing. We have a pipe wrap cushion around the single upright bar so the bikes won't get too scratched up. We strap the bikes to the bar to prevent front to back movement, and to the bottom of the pullout carrier (there are holes in the platform frame for this) with bungees and ratchet straps to prevent side to side movement. This also keeps them from bouncing around as they are strapped downward to the platform, and stay very solid.
Never had a problem. Just be careful exiting driveways and such, go out at angle so as not to drag the ass too much or you'll bend the spare tire carrier bracket - ask me how I know :-)