I've yet to receive one of those that was useful. Meanwhile the 70+ year old storm sirens mounted on the nearby office buildings work perfectly in my experience, being audible even indoors from many miles away.

Even then. During a recent storm, they went off erroneously in Denver. (Looks like the other two erroneous alerts were via phone though.)

> Denver emergency officials say they are working to rebuild public trust after a mistaken tornado siren activation Monday became the third improper emergency alert issued in the city this year.

https://www.cbsnews.com/colorado/news/denver-tornado-alarms-...