Thanks again for your insights and comments Bobby. To answer your question, I do not own any 2 way X-10 devices. My X-10 devices were almost entirely light control, with some outdoor motion detector spotlights which could emit X-10 codes to turn on indoor lighting when motion was detected. I had several appliance modules to switch heavier loads, some pocket RF transmitters to remotely control things, controllers all over the place, some with built in timers / clocks, and not much more. My total investment in X-10 was, at most, a few hundred bucks. It was very easy to walk away from it financially, but I do miss the ability to control everything.
X-10 owners like us are likely to be "control freaks" to some extent, and having a system which acts randomly and erratically defies our "authority". It is frustrating to see the system mis-behave, and even more so while our significant others scoff and smirk and complain when lights begin to randomly turn on, turn off, or not light at all.......... It was extremely easy for me to eventually "pull the plug" on X-10 as my CFL and other noise environment took over control...
I had a long and happy run with X-10, and was indeed an early adopter, probably late 1970's if I had to guess up until the late 1990s for the truly useful and reliable operation. I would call that a success, and thus I had no problem taking it down. Some stuff still remains, and I occasionally look at the Insteon stuff and think about starting over again.
Then I take a deep breath and put down the Smarthome catalog and come to my senses...........