Yes, the RDX shares with other Honda's but is modified feom the CR-V.
"Acura is calling it an all-new, exclusive platform—but the RDX started with the Honda CR-V architecture and modified the chassis and upgraded the powertrain. Obviously, the sheetmetal is much different, too." Motor Trend
SH-AWD on a three-wheeled roller test.
"Here, the Buick and Acura were placed on rollers under each wheel except the left front, so three wheels had zero traction and the one traction surface was under the front not rear wheel. In this case, the Envision could deliver torque to the left front wheel and drive off. The Acura could not and had to be pushed off; it could get going if the wheel still on the ground was a rear wheel. What does this prove? In the occasional circumstance where you’re stopped and both rear wheels and one front wheel are on, say, glare ice, only one car, Buick, will be able to start up without a push."
https://www.extremetech.com/extreme/244191-buick-joins-torque-vectoring-goes-snow-wheel-drive-showThe Active Twin Clutch AWD witb torque vectoring is offered on LaCrosse, Regal, Enclave, and Envision.
I can measure fron hatch to seat back on floor or top of the seat back as if you were carrying a box in our Envision.