We went thru that with my mother. Most of those "Alert" companies are owner by the same outfit. And none are worth it in our opinion. My mother, 92, was very active so we got one with the GPS and all the bells & whistles. Constantly giving erroneous signals, false alerts and too much mis-information. EMT's would show up at her door for no reason.
Agreed that they are a necessary evil, but stay on them and ***** (sorry) and complain as often as it takes for them to get the info correct. And watch your bill. We had too many "oops".
Obviously, we weren't happy with our choice. Best of luck to you.