FWIW...I have both (Denali and RR) and for completely different purposes. There are little details on the Denali that I really like such as cooled seats, step bumper and better highway MPG. But my favorite is the RR due to its excellent suspension and motor (Cal-tuned, of course).
AS I learned from years owning turbocharged Audi cars, the advantages of tuning were endless. So, I had the dealer install the ProCal software after driving in stock mode for about 3 months. The change in performance versus stock was remarkable and the cost-per-horsepower/torque pickup was too...
A couple of thoughts: after driving the RR, I am unsure if you will feel the need to swap shocks or a pipe. The ride is exceptional on all terrain and with 2 presses of a button on your steering wheel, you can open the exhaust. It might not be loud enough for some but it's the first thing I do...
