Installed a Thule Motion XT (L) on my 2015 MDX
First, thanks to all in submitting your input and advice which I reviewed before embarking on a solution to install a cargo carrier on our 2015 MDX with Acura factory rails and crossbars. We liked the functionality and styling of the Thule Motion XT, which is a relatively new product but unfortunately, I did not find any postings on this thread from anyone who had experience with this Thule carrier. Using the Thule fit guide, the Motion XT was one of three Thule products recommended, although based on the roof measurements on the Thule website, the distance from the middle of the front crossbar to the rear hatch was 47.5" or more, but my measurements were closer to 46", so based on that info, the Motion XT (size L) would be too long and interfere with the rear hatch when opened. Fortunately, I decided to go the REI where the staff person and I took some measurements and determined that it possibly would work, albeit very close, so we took the floor model and successfully attached it to our (fixed position) Acura factory crossbars. When opening the rear hatch, the door comes within about 1/4" of touching the carrier, so I think we have a winner! The only issue however, is that when the carrier knobs were completely tightened down onto the crossbars, the bottom of the carrier just barely makes contact with the fin antenna. My temporary solution was to buy a piece of black adhesive felt which I attached to the bottom of the carrier immediately above the fin antenna, but I am now looking for a thicker, more permanent solution such as a rubber or foam covering for the crossbar which would raise the height of the carrier so it would not only prevent contact with the antenna, but also offset the very minor slant due the slanted design of the MDX roofline. I will take and post some pictures shortly, but I am very happy both with the fit and styling of the Thule Motion XT carrier ($649) and the fact that I did not need to purchase the expensive Thule 7602 AeroBlade Edge crossbars and Thule Fit Kit KIT3132, which would have added another approx $500+ to the total cost. I would be interested in hearing from anyone else who has successfully installed either Thule or Yakima carriers, including the Motion XT. Btw, on the freeway drive home from REI, the wind noise was fairly minor and not noticeable with the brief exception of some strong headwinds when it was a bit more noticeable. Lastly, I went with the L (77" length) vs XL (84" length) which is possible but would reach just about to the top of the windshield and barely noticeable from inside the vehicle and would likely pick up additional wind resistance and noise due to the slight upward slope. So if you really need the extra 7" of length, I believe the XL version can work for you on the MDX. I hope this post is useful to other Third Generation MDXers who are looking for a rooftop carrier that will work with their Acura factory rails and crossbars.