It really depends on the installation. I used several X10 devices in a house for years without any trouble. They are powerline communication based, so it's worth testing in the locations you use them. Good installations run fine. Especially for smaller houses, with not a lot of noisy devices already running.jtw said:X-10 is too unreliable to operate an on/off switch? Maybe if I can get confirmation of the switch position it would be ok.