Thanks to all for the interesting replies. I will be canvassing members to obtain details of the locos they intend to use. Then create a data base for all to see. My own system is Roco with the Multimaus and locmause slaves. With the Multimaus I can use 5 digit displays using letters or numbers mixed if I like. These addresses are stored in a library within the controller. They don,t show on the locmaus so I need to allocate addresses within the decoder. I am buying the gaugemaster prodigy to try it out but still like the Roco Multimaus. The Roco system appears to be more powerful than the Gaugemaster and the Multimaus fits the hand better and is easy to use one handed.