Still own a Sonic 13 cu-ft box and now a Motion XT XXL 22 cu-ft box. The SlideLock indicator ensuring all three locks are engaged is absolutely fantastic (over the Sonic). Lets be honest, bags go in, straps go on, and the lid gets pulled down (compressing contents as necessary). I would have bet money a few times all locks were engaged when in fact they were not as indicated by the slide indicator. Box with AeroBlade on '14 Grand Caravan generates very little noise. Positioned the box so the PowerClick clamps were in the middle of their travel. Originally had box positioned as rearward as possible (did not come close to interfering with hatch, but I did not like the amount of rearward overhang, so I centered. 2,000 mile trip yielded 21.6 mpg 55-75 mph driving for 90% of trip with mountains across southern Ohio, West Virginia, Virginia, and into North Carolina.