I just purchased the Thule Frontier box and installed it directly to my MDX roof rack. You have to drill two additional holes for the rear mounts since the cross beams of the MDX rack are a little further apart than the specs for the box, but it is easy to do and the box fits fine. The only potential problem is for those owners who have a spoiler on the rear hatch. With this box, which is long and thin (not the excursion which is short and wide), I think the spoiler would hit the rear of the box when the door opens. Anyone with a spoiler should check this out when ordering a long box. Finally, from my investigation the only Yakima that fits is a metal cage luggage carrier that might meet someone's needs. None of their boxes work yet.