Personally I’d call that a safety issue. A few years ago my wife and I were driving a rental car that was rear ended on the highway by a drunk driver. The impact caved in the left rear wheel and spun us 360 degrees across 3 lanes of the highway. Within a few seconds of coming to a stop an OnStar person was talking to us, asking if we were ok and confirming our location.
We had no clue ahead of time that the rental car had one of these services, but at that moment we were very happy it did. I honestly have no idea about the privacy ramifications, etc. but having been through that experience I’d think long and hard about disabling it outright. I do take my privacy seriously, but I’d have to weigh that against the safety of me & my family in that kind of situation and disable it only as an absolutely last resort… Just my own personal $0.02 on the matter.
I think my car only came with a free trial for that service, I think you needed to pay after a certain amount of time. Cell phone works well enough for me.
I estimate that the probability of injuring my arms and that no one else is around to call for help is low enough to not be worth the monthly subscription.
It's incredibly unlikely that you'd be in such a bad accident that you couldn't call for help; while simultaneously being isolated from the public to the point nobody saw your accident and started calling ems/police before you could.
That's not to say it doesn't happen; but I definitely wouldn't be worried about it.
You obviously don't live or drive in a semi-rural area at night with larger wildlife that tends to dart across the road in front of cars. All it takes is hitting a deer or javelina hard and going into a ditch.
Playing devil's advocate, in a crazy accident you may not be able to get to/reach your phone, or even be responsive. If you use the personal assistant function on your phone, it's no different than using OnStar, in terms of privacy.
All of this said, last I heard OnStar was pretty expensive for the average household income. I don't have it, and I don't worry too much about it.
That depends a lot on where you drive. I've been in situations where, if I had hit a moose, there would have been no one around to call for help except the moose (assuming it had survived the collision, but they often do if it's a smaller vehicle). That stretch of road didn't get many passers-by on snowy Sunday nights in January. Maybe a half-dozen vehicles an hour. Combine that with poor visibility, and it could have been a long time before someone noticed and called for help. Fortunately, I never did have an accident along that stretch.
Of course, if you're only driving in built-up areas or along major transit corridors instead of in awkward parts of northern Ontario in the middle of winter, your chances of having someone call in for you are much higher.
I think OnStar is satellite-based, so it might reach areas where cell service doesn't. I believe the stretch of highway I was thinking of (Ontario highway 655) does have at least partial cell coverage now, although it didn't at the time when I was driving it regularly. It isn't extremely remote—it would take emergency services from Cochrane or Timmins about half an hour to reach the farthest point, so they might get there in time, depending on what exactly the damage was.