Any device that might encourage safe driving and help reduce teenage fatalities has appeal, so long as privacy protections are in place to prevent misuse of the data or surprise for consumers.

While the CarChipE/X and the RS-1000 both aim to improve teen driver safety, the RS-1000 has more features to monitor—and hopefully correct—bad habits. The fact that the RS-1000 can sense cornering forces in addition to hard acceleration and braking is key, and its instantaneous warnings and progressive alarm are more useful than the delayed warnings of the CarChipE/X.

We also liked the RS-1000's friendlier software and reporting. However, the RS-1000 carries additional installation challenges; its larger size makes it difficult to find a discrete location, the cable must be carefully routed, and there are optional connections to be made for seat belt and brake light sensors. It is also about $80 more expensive than the CarChipE/X.

The small size, lower price, and code reading capability of the CarChipE/X may be appealing to some buyers. But if the real goal is to discourage bad driving habits, the RS-1000 is a better choice.

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