Personally, I'd buy the Touareg for your towing. It will drive like a RWD SUV (the XC90 drives like a FWD), it has a wider track (more stable), better brakes (multi-piston Brembos with larger rotors), better turning radius (by 2 feet), wider tires (better footprint), and it weighs 500 pounds more. It's simply a better TOWING vehicle.