I have an EasyDCC system built into a portable HO scale test-track type of setup that I use at home and at a club for programming decoders, because I have found it to be easier to use than some of the others. It will program QSI and other sound decoders when other systems won't.
Having it portable allows me to intall and program decoders without having to shut the main layout's DCC system off if other members are running trains. During our club's open houses, we run the outdoor portable modules using it.
For my G-scale outdoor trains, I use CVP's AirWire900 wireless DCC receiver/decoders in all of my locomotives, and run them from battery power. Being completely wireless, I never have to worry about dirty track or complicated wiring because of the numerous reverse and turnaround loops on my layout.
A friend has the EasyDCC wireless system on his HO scale home layout, including their stationary decoders to control his turnouts, and has been very satisfied with it.
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