I suspect environment and product really really matters.
I got a set about, oh, 10-15 years ago that were terrible. They connected, sort of, but always dropped out.
Then I got one with a STB and it worked pretty well as a point-to-point device -- it was only providing access to the STB and never had any issues.
I replaced them when I upgraded that home network with four TP-Link devices, and they worked brilliantly and included Mesh-Wifi Repeaters. Once they were all synced up I changed the default powerline encryption keys.
I wouldn't trust them to stand up to anyone trying to break in, but it'd be fine for a basic home environment.
I got a set about, oh, 10-15 years ago that were terrible. They connected, sort of, but always dropped out.
Then I got one with a STB and it worked pretty well as a point-to-point device -- it was only providing access to the STB and never had any issues.
I replaced them when I upgraded that home network with four TP-Link devices, and they worked brilliantly and included Mesh-Wifi Repeaters. Once they were all synced up I changed the default powerline encryption keys. I wouldn't trust them to stand up to anyone trying to break in, but it'd be fine for a basic home environment.