Have you considered a 550ix MSport? The RR is indeed sexy as hell, but I would be concerned over reliability. However, I also agree with the poster here who recommended the Cayenne GTS if it's a sporty SUV you're desiring.
Currently: 2015 Porsche 911 GTS and 2016 Cayenne S eHybrid
Past BMWs: `05 645CiC; `07 650i; `08 M6 convertible; '08 135i; `11 750ix MSport; `15 M235i convertible
"You think that's air you're breathing now?"