I use the AUX port and find advantages in doing so.
For one, I can operate accessories that are powered by a source not going thru the TIU, or even those that are powered thru the TIU but not Port #1 (a dumb idea to me anyways) using my remote.
For switches I use external power on them, not track power. So by using AUX, I can control action of switches without power applied to the track. There's lots of advantages in this.
Another is for lighting that uses an separate power source. I can turn them on and off using my remote without having power on the rails.
While I don't have operating accessories controlled by DCS, I imagine the concept above would apply here too
Being able to control things without having power on the rails is a big plus.
Both situations obviously require the switches and lights and accessories to be programmed into your DCS system
- walt