The mini-breakers (pictured on the right in Joe's first photo) are still manufactured and sold. As to their reliability, as a child I lived in a run-down third-storey walkup where all the outlets and lights were controlled by a single fuse (replaced by a 15-amp minibreaker).
The thing was pretty reliable and it always "popped" when we had too many high-amperage things plugged in at once. Of course, I can't speak for other people's houses.
What I do remember is that the buttons are hard to press (which could be an issue with people with arthritic hands).
