The WS13A will do the job:...
Well it certainly is the best switch I've seen for the application. The main drawbacks for my application is that I'd like it to
not respond to an all lights on. I can live with that limitation by putting it on a different house code, however. I would like it to default to the off condition in the event of a power interruption like the wall switches do.
Does it? Also the style of the switch will be a bit inconvenient sharing a box with 1 or 2 other conventional X10 or regular switches. I'd need some form of custom wall plate cover like I had to use for my X10 test box. My test box has a GFI protected outlet in the middle of a power switch and a standard outlet. The GFI outlet needed a similar rectangular hole like the WS13A needs. (Since one of the test items involves plugging in a wire to the live side of the outlet, I wanted to make sure I had the extra protection of the GFI.)
I also need to make sure I have a neutral wires at the two boxes where I have fans.