OnStar FMV, which goes on sale Sunday, costs $374.99, including installation, and no less than $18.95 a month.

OnStar, a General Motors service that provides emergency assistance, will be available to all vehicle owners beginning Sunday, July 24 at Best Buy stores nationwide.

“The wait is over,” OnStar President Linda Marshall says in a GM press release. “Since we announced OnStar FMV at the Consumer Electronics Show in January, thousands of people have signed up to be notified when this innovative product is ready to buy. Now, through Best Buy, they can enhance their Fords, Toyotas, Chryslers and other brands with the power of OnStar.”

GM says OnStar FMV (For My Vehicle) works on more than 90 million vehicles, but shoppers interested in the product should use GM’s vehicle selector to determine if their vehicle is compatible.

Owners with compatible vehicles will pay a monthly fee for the service, just like GM vehicle owners. The rear-view mirror costs $374.99, including a $75 installation fee. Services plans start at $18.95 a month.

OnStar FMV offers the same core services available on GM vehicles (automatic crash response, turn-by-turn navigation, hands-free calling, stolen vehicle location assistance, emergency services and roadside assistance), but the Detroit Free Press says the unit is not as sophisticated as the one pre-installed on GM models. “The unit is not integrated with a car's sound system. So as commands issue from the mirror, such as turn-by-turn directions or an incoming call, the car stereo is not briefly quieted as it is in an OnStar-equipped GM car. This can make the prompts a bit hard to hear.” The Detroit Free Press adds that OnStar FMV does not issue vehicle diagnostics.

Inside Line and the Detroit Free Press conclude that OnStar FMV is GM’s latest move to compete with Hyundai’s Blue Link, Ford’s MyFord Touch and MyKey technologies and smartphone applications. “It will be interesting to see whether consumers snap up GM's security blanket — or just opt to use their mobile phones,” says Inside Line.

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