Daniel:

One thing that I have found, having used the Leviton's now for approx 4 months -- their implementation of preset dim does not follow a de-facto industry standard (as set by PCS). So, if my home controller (SmartLinc HouseLinc) sends a command to the Levitons telling them to go to, say, 40% of full bright, they do not see this command. Both SmartLinc, PCS and others follow a standard that PCS implemented some time ago. For whatever reason, Leviton chose an incompatible approach, and I am not aware of any X10 home controllers that support Leviton on this. Other than this short-coming, the switches work well, and are reasonably resistant to noise. However, if you are seeking to control these switches through an IR543, you may have to put a repeat on some of the commands, depending on the cleanliness of your house power -- even though the Levitons are resistant.