(Don't worry, there's an Xbox 360 hiding down there. The Mac Pro sits there and looks pretty ^^)
Playing Forza 4 with the wheel is so much more pleasant than playing with the controller, despite not having vibration. There is simulated force feedback with a spring on bungee cord (fixed spring constant, unfortunately) inside. I'm also a little sad that the paddle shifters don't reach down to my ring fingers with my hands at the 9 o'clock and 3 o'clock positions, nor are they fixed to the steering column.
There definitely is merit to having a driving simulator when one has the potential to track in a nice car in real life: traveling to various tracks around the world with said car is quite impractical. Also impractical is owning the fleet of cars available in the game.