Nothing. I purchased this car six years ago, raced it on the track and in autocross events, drive on weekends or to work (10 miles) on a nice day and it just runs great. These cars defy the laws of physics once you learn how to drive them. I had a 928S-4 for a while and it was expensive to run but god-awful fast.
This is an amazing car and mine is actually quite cheap to run, it's very fast and corners likes it's on rails, so I hope you have fun with yours.
Jonathan.