Rob, Its not easy atall. You cant just moniter top speed, Say for example they go on a track like aston with fast straights. That can be fast speed. Then they goto a track like South City. They will have complety different top speeds. There is no way ever you will get the same top speed on SO then on Aston. Acceleration is a partial factor, but again, Isnt easy. If they go down a hill, They will change again. It will be hard to make a solid app that doesnt get the wrong people and yet, still catchs cheaters.