Hopefully they will be reliable. The ones used on aircraft are pretty well defined -- who knows what they will put in your car.

But, in some ways it's better -- at least you now about it. Cops have been pulling records from things like OnStar -- without knowing how reliable the data was. I think that in some cases, the logging was just for the company's own benefit, and definitely could have bugs.

But, it gets presented as a computerized record, and they're never wrong.

hj