I have been having speedo problems and wondering if this is going to be an ongoing problem. So I thought I might be better off replacing the stock unit with an aftermarket unit. The unit cost a little more but if I need to replace the stock speedo sensor a 2nd time it will pay for this unit. Is this speedo problem something that I wont have to worry about in the future or should I take the plunge and replace it with this unit? Does anyone use one of these on there S3? Pros and Cons? Anyone?