I am quite sure LR do more than just make the exhaust loud to produce the SVR
Not saying it is a sin to have fun in your Range Rover, but why not have fun in it, with what it is designed for? Go play off-road, you'd be very pleasantly surprised, and given a great adrenaline rush, at what these beasts can do, when thrown about. I suspect if you took it to the extreme of what it is built for you would be desperate to do it over and over, you would never think of 'big wheels and a little bit of noise from the exhaust' as fun again. Still each to their own.