Not an expert biker, here. But, unfortunately, I am fairly well experienced in buying cheap bike carriers. Have had several. The less expensive ones end up costing more when they fall apart and you have to buy the next one up. And do it all over again... and again. The cheaper ones with rubber straps, for example, break with not much UV damage. The riveted frames don't last long either. Sure... you can go to using your own straps and drilling out the loose rivets and replacing with bolts, etc, if you want to. My experience says to go with the best (highest review rated) bike rack you can afford... the first time.
Lately, I have been very satisfied with
This One from Camping WorldEdit: Oops... Looks like Campfire Time (above) has proven, yet again, Amazon beats the Camping World Internet Price. LOL