Im looking for a solid cargo box to fit on my Yakima rack system, I still need to be able to carry 4 whitewater boats. But the box needs to be long enough for paddles, gear ect. Ive narrowed it down to either the Rocket Box 11, or the Sky Box 12 both by Yakima. Anyone have any experience with either of these boxes? Any feed back? I helped my buddy put his rocket box on his subaru today at work and it just seems way too flimsy.