Was never a fan of racks that attach to the bike's top tube and hang. They bang into one another and wear the paint and cables. They allow the bikes to swing and puts the weight high on the rack which exacerbates a bouncing effect, especially with more than 2 bikes. Heininger is a brand I have never heard of. I would stick to trusted brands like Thule, Yakima, Swagman etc with a tire mounted design and a threaded pin to mitigate play in the receiver. You will spend more money, but you get what you pay for.
Here is an example of the rack I have. Had it for almost 10 years and never an issue.
Swagman XC