As of July 2015, the Rightline Gear Sport 3 Car Top Carrier, Reese Explore Expandable Cartop Carrier and X-Cargo Sport 20 Car Top Carrier are well-rated rooftop cargo carriers. Rightline's carrier earns four out of five stars online at AutoAnything. Reviewers say that it is high-quality and a good size.
On Walmart's website, the Reese carrier averages 4.4 stars. Top reviews state that the carrier is flexible, expandable, very sturdy and a good value. In addition, cargo stays dry in the rain.
Kmart's online ratings average 4.5 stars for the X-Cargo carrier. Reviewers explain that the product is easy to install, does not vibrate and provides a large amount of extra room.