Mph. Sometimes it's just the info you need to do or require a certain part. As we all know the BMW engine is fairly bomb proof its just all the other stuff that goes with it. Given the accessability of parts most competant mechanics would be able to work on an Aero wheather they choose to do so is a different matter. After many years of ownership the rear wheel bearing did it for me, no info from the factory Si fab wanted nearly five times of what I eventually had one for and got the jitters pressing the old one out of the cage where do you get another cage if you crack it. Let's not get started on bodywork your into specialized metal work if you have anything but a small dink. But what a glorious car the Aero is I do miss it. The Aero will also pass anything on the road in front of you except perhaps a petrol station. Go on you know you want too..... Em