It is very important for you to consider your layout power wiring, your command bus or network wiring and in some cases separate feedback bus wiring.

With DCC the signal and the power go hand in hand so your locomotive must have good conductivity to insure reliable train control. DCC is more tolerant of dirty track than some other command control systems because of the fact that DCC commands are sent over and over to the decoders. Nevertheless, periodic track cleaning will still be needed.

Adapted from "Digital Command Control: The Wave of the Future", by Zana and A.J. Ireland.