With the dual-side opening, the box is one of the most up-to-date options from Thule. As one of the best all-around cargo boxes, the Sonic offers impressive aerodynamic performance as well.

It's a misnomer—the blocky dimensions add drag and reduce fuel economy. Which is why Thule's new Sonic Alpine 663 is so smart. It's longer, thinner, and more aerodynamic than most, so it doesn't ...