I've used x10 on and off since the early 80's. And... it sucks. When it works, it's cool, fun and cheap. But reliable it's not. For starts, all the inexpensive

I've used x10 on and off since the early 80's. And... it sucks. When it works, it's cool, fun and cheap. But reliable it's not. For starts, all the inexpensive units I've used only support one-way commanding and the commands are susceptible to collision. Send a command to turn a light off and just hope that it goes off. Want to dim a light? All the commands are incremental so you'll have to do stuff like send 8 dim commands to get to a known minimum state then send 4 brighten commands to brighten to the desired level. And since it's one-way with no acknowledgments, you just hope that your commands were received and that the light was on to start with. Fun to play with, but I'd never trust it for anything but toy usage.