got me curious about that!.. next time I am on a ladder changing the garage light bulb I will see if I have a sticker like that.
as for stability, I went to lowes yesterday and bought a couple/few z wave dimmers/switches, so now I have a broader mesh network. This definitely helped with the garage door opener. Every so often on a Z wave repair I would get an error about the garage door in regards to the mesh network (That went away after installing more z wave devices/repeaters).