Nothing compares to a motion simulator. One wasn't enough, so I purchased two so my buddies and I can race head to head.
The SimGear simulator has become a valuable tool for our team and drivers. We run sessions on the simulator before every away race we participate in and it has helped give us an edge that is impossible without actual practice at the track.
Having a SimGear simulator really makes you not want to go back to console driving games. The realism is just unmatched.